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Expository Text Looking Further The Hubble Telescope by Bill Nagelkerke PAIRED READ The Watchers CV_CR14_LR_G6_U5W4L60_E_118740.indd 2 24/02/12 3:29 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF STRATEGIES & SKILLS Comprehension ELL Vocabulary Strategy: Reread Skill: Sequence data, distorts, orbit Content Standards Vocabulary Strategy Science Earth and Space Science Context Clues Vocabulary colleagues, conservatively, deduction, droned, galaxies, sustain, ultimately, verify Word Count: 1,935** Photography Credit: NASA, ESA, and G. Bacon (STScI) **The total word count is based on words in the running text and headings only. Numerals and words in captions, labels, diagrams, charts, and sidebars are not included. Copyright © The McGraw-Hill Companies, Inc. All rights reserved. No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written consent of The McGraw-Hill Companies, Inc., including, but not limited to, network storage or transmission, or broadcast for distance learning. Send all inquiries to: McGraw-Hill Education Two Penn Plaza New York, New York 10121 ISBN: 978-0-02-118740-9 MHID: 0-02-118740-1 Printed in the United States. 1 2 3 4 5 6 7 8 9 DOC 15 14 13 12 11 10 A IFCIBC_CR14_LR_G6_U5W4L60_E_118740.indd 2 24/02/12 3:29 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Essential Question How does technology lead to discoveries? Looking Further The Hubble Telescope by Bill Nagelkerke Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Chapter 1 Land or Sky? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Chapter 2 The Amazing Hubble . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Chapter 3 Hubble’s Last Days . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 NASA, ESA, S. Beckwith (STScI) and the HUDF Team Respond to Reading . . . . . . . . . . . . . . . . . . . . . . . . . 18 PAIRED READ The Watchers . . . . . . . . . . . . . . . . . . . . . . 19 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Focus on Science . . . . . . . . . . . . . . . . . . . .24 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 1 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Introduction The two parts of the word telescope come from the Greek language. Tele means “far” or “a long way,” and scope means “to see.” A telescope is a tool that helps you see things that are far away. An ancient Greek man named Aristarchus was the first person to think that Earth went around the sun. He made this deduction without a telescope to verify it. He lived before telescopes were invented. He had to study the sky using just his eyes. In 1609, the Italian scientist Galileo made a refracting telescope. He used it to study the sky. Refracting telescopes bend light through a glass lens. This makes objects that are far away look bigger. One of Galileo’s telescope Galileo Through his telescope, Galileo discovered sunspots and Jupiter’s moons. (t) NASA, ESA, S. Beckwith (STScI) and the HUDF Team, (b) National Geographic Society/Corbis telescopes could make objects look up to 20 times bigger. 2 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 2 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Several decades later, another astronomer, or someone who studies space, made a reflecting telescope. The astronomer’s name was Isaac Newton, and his telescope used mirrors instead of lenses. The Hubble Space Telescope is a reflecting telescope. Hubble has helped astronomers see deep into space. It has discovered galaxies never seen before. Hubble has helped scientists understand some things they did not understand before. It has also shown scientists some new things they do not understand yet. Today’s astronomers do not need to look through telescopes to see things. Instead, they look at pictures recorded by the telescopes. This is how the Hubble NASA-STScI telescope works. The United States and Europe have worked together to make the Hubble telescope. Hubble Space Telescope 3 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 3 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Chapter 1 Land or Sky? Astronomers began to explore the universe with telescopes. They discovered many new things. For example, when Galileo looked at the moon through his telescopes, he saw that it was covered in craters. Before this, people had thought that the moon was smooth. Over time, telescopes became bigger and better. In 1873, the Alvan Clark company’s refracting telescope helped scientists discover the two moons that orbit Mars. The Lick Observatory in California was built in 1887. It was the first permanent mountaintop observatory. In 1897, the Yerkes Observatory in Wisconsin opened. Yerkes Observatory has the world’s largest refracting telescope. The lens in the telescope is 40 inches wide. Language Detective crra crater c att Bigger and better are comparative adjectives. Find a superlative adjective on this page. Through his telescope, Galileo was able to see the craters on the moon. 4 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 4 (t) NASA, ESA, S. Beckwith (STScI) and the HUDF Team, (b) StockTrek/Getty Images moon 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF The atmosphere around Earth distorts the light coming from space. This means telescopes on Earth cannot see some objects in space clearly. A German scientist named Hermann Oberth had an idea to solve this problem. His idea was to send a telescope up into space on a rocket. The telescope would orbit high above Earth so scientists could see things clearly. Four satellites carrying telescopes were sent into space between 1966 and 1972. Different Kinds of Telescopes Optical and radio telescopes are two kinds of telescopes. Optical telescopes catch the light we can see with our eyes. The Hubble telescope is an optical telescope. NASA Radio telescopes use radio waves to make images, or pictures. Radio waves are invisible to us. They can come from objects such as stars and galaxies. One satellite that carried a telescope was called Copernicus. 5 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 5 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF The U.S. government agreed to build the Hubble Space Telescope in 1977. Ultimately the space shuttle Discovery carried the Hubble into space in 1990. Hubble now orbits 353 miles (568 kilometers) above Earth. Hubble takes pictures of outer space. These pictures are some of the clearest pictures ever seen of celestial objects. Hubble looks much like a regular telescope. The main difference is its solar panels. The solar panels harness sunlight to give power to Hubble’s computers and other instruments. In Other Words capture sunlight. En español, harness sunlight quiere decir hacer uso de la luz del sol. The Hubble Space Telescope solar p panels NASA, Illustration: Carlos Aon Hubble’s b bble’s solar panels nels harness sunlight. l light. The space shuttle Discovery blasts off, taking Hubble into orbit. 6 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 6 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Hubble At first things did not go robotic arm well for Hubble. Scientists found a problem with the telescope’s main mirror. There was also a problem with the solar panels. These problems were not fixed until 1993. In 1993, NASA sent the space shuttle Endeavour to repair Hubble. The astronauts on Endeavour repaired the problems. Astronauts used the space shuttle’s robotic arm to repair Hubble. The shuttle mission was a great success. It showed that astronauts could repair Hubble while it was orbiting Earth. Hubble could have a long life. Hubble was able to see much more than other telescopes. It sent large amounts of information back to scientists on Earth. STOP AND CHECK Why is it important to have a telescope in space? Edwin Hubble NASA-STScI The Hubble Space Telescope was named after a famous American astronomer, Edwin Hubble. Hubble worked at the Mount Wilson Observatory in California in the 1920s. He studied spiral nebulae, or clouds of dust and gas in space. 7 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 7 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Chapter 2 The Hubble can be thought of as a kind of time machine as well as a telescope. Objects in space are very far away. Some galaxies are so far away that their light takes billions of years to reach Earth. Hubble can take pictures of these galaxies. The pictures show what happened billions of years ago. Once, Hubble was pointed into an area of space that seemed to have nothing in it. After ten days in the same position, Hubble sent back pictures of thousands of new galaxies. This area of space is now called the Hubble Deep Field. Scientists have used the data from Hubble to help determine the age of the universe. Information from Hubble has helped scientists discover that the universe is expanding faster than before. Some scientists had thought it was slowing down. (t) NASA, ESA, S. Beckwith (STScI) and the HUDF Team, (b) NASA, ESA, and M. Livio and the Hubble 20th Anniversary Team (STScI) The Amazing Hubble Hubble’s amazing images have shown the beauty of space. clouds of gas 8 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 8 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF NASA scientists control Hubble by sending radio messages to a satellite. The satellite sends the messages to Hubble. These messages tell Hubble where to look and what to look for. The computers on Hubble record everything Hubble sees in space. Hubble then sends that information back to Earth. Scientists send the data to the Space Telescope Science Institute in Baltimore. Scientists at the institute study the data. Their colleagues around the world can download the data from the Internet. Then they can use the data in their own research, too. Capturing Data from the Stars This diagram shows how the information gathered by Hubble is sent to the Space Telescope Science Institute. 1 2 Data 3 1 Starlight 2 Hubble Space Telescope 6 3 Tracking and Data Relay Satellite 4 Ground Station, White Sands, NM Illustration: Carlos Aon 5 5 Goddard Space Flight Center, Greenbelt, MD 6 Space Telescope Science Institute, Baltimore, MD 4 9 001-009_CR14_LR_G6_U5W4L60_E_118740.indd 9 24/02/12 3:32 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Young scientists also can study Hubble’s discoveries. College students can work with people at the Space Telescope Science Institute. These students can study Hubble data and hear speakers talk about space and astronomy topics. The institute has set up the Hubble Deep Field Academy Web site for younger students. Students have a chance to experience what it’s like to receive Hubble data. The academy helps younger students understand the images Students can use the Hubble Deep Field Academy Web site to study information from Hubble. students Ariel Skelley/Blend Images/Getty Images from Hubble’s Deep Field. 10 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 10 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF This is the deepest Deep Field picture yet. galaxy It can be hard for academy students to understand distances in space. Something that looks small may be closer to Earth than something that looks big. Astronomers use light to help measure these distances. A light-year is the distance that light can travel in a year. Light can travel about 6 trillion miles in one year. That is 6,000,000,000,000 miles! One object in the Deep Field is about 12 billion light-years away from Earth. It would take 12 billion years NASA, ESA, S. Beckwith (STScI) and the HUDF Team for light from this object to travel to Earth! STOP AND CHECK What are some of the things Hubble has shown astronomers? 11 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 11 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Chapter 3 Hubble’s Last Days In 1997, there was a second space shuttle mission to a new camera called a spectrometer. The spectrometer can take pictures of infrared light that comes from galaxies that are very far away. The astronauts also installed a spectrograph to help Hubble look for black holes. In 1999, astronauts replaced all of Hubble’s gyroscopes. Scientists on Earth use gyroscopes to point Hubble in different directions. Hubble has six gyroscopes. It was obvious from all the repairs that Hubble had been (t) NASA, ESA, S. Beckwith (STScI) and the HUDF Team, (b) NASA Hubble. Astronauts on the space shuttle Discovery installed working hard. Hubble is attached to the space shuttle so astronauts can safely make repairs. space shuttle 12 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 12 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF In 2002, astronauts installed another type of camera in the Hubble. This camera could see more and record better images, and was faster than the other cameras. The astronauts also replaced the solar panels with smaller panels. The new ones made more power. The last trip to Hubble was in 2009. On this trip, astronauts replaced and changed equipment. These changes will help Hubble stay in orbit for as long as possible. The shuttle program is now finished, so shuttles won’t visit Hubble anymore. Language Detective The word better is a comparative adjective. Find another comparative adjective on this page. Deep Field and Ultra Deep Field Illustration: Carlos Aon Hubble Space Telescope In 2004, Hubble sent an image called Ultra Deep Field. It showed about 10,000 galaxies. Hubble Deep Field (1995) Hubble Ultra Deep Field (2004) 13 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 13 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Hubble’s one-millionth observation was made on July 4, 2011. It was of a planet that scientists call HAT-P-7b. This is an artist’s view of the planet and the star it is orbiting. Scientists believe Hubble will stay in orbit for a few more years. If it lasts until 2015, it will have been orbiting Earth for 25 years. Hubble’s life was conservatively estimated at only 15 years! When Hubble stops working, it will fall back to Earth. Hubble was made to work with space shuttles, but the space shuttle program ended in 2011. Until it stops working, Hubble will continue to discover all sorts of amazing things. Hubble has helped humans to look further into space than ever before. One day Hubble will no longer be orbiting Earth, but NASA, ESA, and G. Bacon (STScI) most likely, Hubble will not be the last telescope in space. 14 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 14 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Hubble Facts • Hubb Hubble ble weighs 24,500 pounds, or as much as two ll full-grown elephants. • Hubble orbits around Earth once every 97 minutes, at about 5 miles per second. • Hubble orbited Earth more than 100,000 times in its first 20 years. • Hubble can see ten times more clearly than the best telescopes on Earth. • When scientists move Hubble to focus on a faraway object, it is like shining a light onto a small coin that is 200 miles (320 kilometers) away. • If you could see as well as Hubble can, you could stand in New York City and see two fireflies in San Francisco. (bkgd) NASA, ESA, S. Beckwith (STScI) and the HUDF Team • The data collected by Hubble so far would fill about 6,000 DVDs. 15 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 15 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF In 2003, NASA introduced the Spitzer Space Telescope. This telescope was designed to study infrared light. It has discovered planets outside our solar system. The Spitzer Space telescope has also discovered the largest ring around Saturn. There are plans for more orbiting telescopes like Hubble and Spitzer. One of these orbiting telescopes is the James Webb Space Telescope, or Webb telescope. The Webb telescope will carry special cameras and spectrometers. A huge sunshield will protect the telescope from the sun’s radiation. The Webb telescope’s main job will be to study the history of the universe. STOP AND CHECK Why will Hubble stop working eventually? NASA Scientists hope the Webb telescope will look back to the origins of the universe. 16 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 16 24/02/12 3:36 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Conclusion The Hubble Space Telescope is one of NASA’s most successful missions. The pictures Hubble has sent back to Earth have amazed people around the world. Scientists are planning new things for space telescopes. The Webb telescope will have a mirror seven times bigger than the mirrors in Hubble. Scientists also will study the sky using telescopes on Earth. These telescopes will be more powerful than Galileo ever imagined. One of these telescopes is the Square Kilometre Array. There is a lot more work for astronomers to do, and Panoramic Images/Photodisc/Getty Images there are many more exciting discoveries to be made. satellite dish The Square Kilometre Array will have 3,000 radio telescopes like these 17 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 17 24/02/12 3:37 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Summarize Respond_Bhead_60-80 Event UseRespond_text_60-80 details from Lookingxxxxx Further to summarize howxxxxxxxx telescopes xxxx have xxxled xxxxxxx to newxxx discoveries. Usexxx your xxxx graphic xxxxxorganizer xxxxxxxxxxxx to help you. xxxx Respond_Bhead_60-80 Text Evidence Respond to Reading_numblist_60-80* RUN-IN_BLUE_ 1. What features tell you that Looking Further is an L50-80 expository text? GENRE Respond to led Reading_numblist_60-80* 2. What steps to the development of RUN-IN_BLUE_ telescopes that L50-80 stay in space and orbit Earth? SEQUENCE Respond to Reading_numblist_60-80* 3. What is the meaning of the term spiralRUN-IN_BLUE_ nebulae on L50-807? What kind of context clue can you find to page help you figure out the meaning? CONTEXT CLUES 4. Respond to Reading_numblist_60-80* RUN-IN_BLUE_ L50-80about how telescopes have changed from how 4. Write they were in Galileo’s time to how telescopes are today. Use the text to help you. WRITE ABOUT READING 18 010-018_CR14_LR_G6_U5W4L60_E_118740.indd 18 24/02/12 3:37 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Compare Texts Read a story about how scientists used telescopes to make an unusual discovery. The Watchers The spaceship began orbiting the planet. The ship’s crew had d named the planet Elektron. Elektron was the old Greek word for amber. Amber is a spaceship resin that can create sparks of electricity. The ship’s crew had found another planet that could sustain ain human life. They all watched the he planet SK-ope. The close-up views they y could see through it were bringing the to llife. h planet l f The crew was excited. They had survived last night’s space storm, and their mission was almost finished. “It looks just like Old Earth!” Illustration: Carlos Aon “The telescopes have found us the perfect place to live!” In Other Words making it look real. En español, bringing the planet to life quiere decir haciendo el planeta más real. 19 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 19 24/02/12 3:37 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF The crew turned away from the SK-ope and started to talk. Commander Diaz stayed by the SK-ope. The data from the deep-space telescopic probes was clear. The crew had been searching for a planet like this one for years. The evidence was too good to ignore. And yet … Diaz felt that something was horribly wrong. She looked more closely at the SK-ope. Suddenly the hairs on the back of Commander Diaz’s neck stood up. It was as if they were charged by electricity—by the planet Elektron below?! “Shall we take the ship down, Commander Diaz?” asked Second Officer Nowak. At first Diaz hesitated. She had no reason not to give the order, however. The scientific data showed it was safe to land. So, finally, Commander Diaz gave the order to land. The engines droned as the ship slowed and the landing equipment unfolded. Diaz stayed at the SK-ope. She was staring at the screen. “Commander? You should buckle in,” Nowak said. Commander Diaz was silent. Nowak asked, “What is it?” 20 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 20 24/02/12 3:38 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF screen Commander Diaz asked, “Can we stop the ship from landing?” Nowak replied, “It’s too late. What did you see?” Diaz said quietly, “I saw people. They were looking at me with their own kind of SK-ope.” Nowak asked, “Who … what … Diaz are they?” “They’re Watchers. That’s what they were doing. They were watching and waiting.” Diaz turned the SK-ope to its lowest level. She wanted to keep the terrifying pictures from her crew for as long as she could. The pictures were of faces they had seen before. The pictures were of Nowak’s face and her own face looking back at her. The watchers looked exactly like them. Illustration: Carlos Aon Make Connections How did the scientists use technology to discover the planet Elektron? ESSENTIAL QUESTION How do Looking Further and The Watchers help you to understand the importance of telescopes as tools for exploring the universe? TEXT TO TEXT 21 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 21 24/02/12 3:38 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Glossary atmosphere the gases that surround planets, including Earth (page 5) black holes parts of space with such strong gravity that not even light can escape, making them appear to be empty (page 12) celestial relating to the sky (page 6) infrared light a type of light that cannot be seen but is given off by objects above a certain temperature (page 12) NASA National Aeronautics and Space Administration, the U.S. space exploration agency (page 7) observatory a place with equipment to study the sky (page 4) spectrograph a device that can split light into its different colors and photograph them (page 12) 22 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 22 24/02/12 3:38 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Index Aristarchus, 2 Deep Field, 8, 10, 11, 13 Galileo, 2, 4, 17 Hubble, Edwin, 7 James Webb Space Telescope, 16, 17 Newton, Isaac, 3 space shuttle, 6, 7, 12, 13 Space Telescope Science Institute, 9, 10 telescopes – optical, 5 – radio, 5 – reflecting, 3 – refracting, 2, 4 Ultra Deep Field, 13 23 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 23 24/02/12 3:38 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Purpose To understand the difference between refracting and reflecting telescopes Procedure You will need poster paper or board, glue, and markers. Step 1 Choose a partner. Read Looking Further again. Write down facts about refracting and reflecting telescopes. Step 2 Use an educational Internet site to find out more information about refracting and reflecting telescopes. Find a diagram of each type of telescope. Step 3 Make a poster with information about the history of each type of telescope. Draw diagrams to show how each type of telescope works. Conclusion What did you discover about the refracting telescope and the reflecting telescope? How are the two telescopes different from each other? 24 019-024_CR14_LR_G6_U5W4L60_E_118740.indd 24 24/02/12 3:38 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Literature Circles Nonfiction The Topic What is Looking Further mostly about? Text Structure How does the author organize information in this book? How does this organization help you understand how telescopes have changed? Conclusions What is the most important thing you learned in Looking Further? What do you think will happen in the future with telescopes and space exploration? Author’s Purpose Why do you think the author wrote this text? What were the main points the author wanted the reader to understand? Make Connections What other books have you read about exploration of our universe? How were the books you read the same as this one? How were they different? IFCIBC_CR14_LR_G6_U5W4L60_E_118740.indd 3 24/02/12 3:29 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF Breakthroughs Science GR V • Benchmark 60 • Lexile [t/k] Grade 6 • Unit 5 Week 4 www.mheonline.com ISBN-13 978-0-02-118740-9 MHID 0-02-118740-1 99701 EAN 9 780021 187409 CV_CR14_LR_G6_U5W4L60_E_118740.indd 1 6 24/02/12 3:28 PM Program: CR 14 Component: LR Vendor: Learning Media Level: 60 G6 U5 W4 E PDF