CXECA08ARD_G3U2_OLR_Cvr 3 9/19/06 9:38:37 AM Copyright © by Harcourt, Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publisher. Requests for permission to make copies of any part of the work should be addressed to School Permissions and Copyrights, Harcourt, Inc., 6277 Sea Harbor Drive, Orlando, Florida 32887-6777. Fax: 407-345-2418. HARCOURT and the Harcourt Logo are trademarks of Harcourt, Inc., registered in the United States of America and/or other jurisdictions. Printed in Mexico ISBN-13: 978-0-15-352338-0 ISBN-10: 0-15-352338-7 1 2 3 4 5 6 7 8 9 10 050 15 14 13 12 11 10 09 08 07 06 If you have received these materials as examination copies free of charge, Harcourt School Publishers retains title to the materials and they may not be resold. Resale of examination copies is strictly prohibited and is illegal. Possession of this publication in print format does not entitle users to convert this publication, or any portion of it, into electronic format. Faster Than a Speeding Bullet . . . . . . . . . . . . . . . . . . . 2 Every Color of the Rainbow . . . . . . . . . . . . . . . . . . . . . 4 Bounce Off or Take In? . . . . . . . . . . . . . . . . . . . . . . . . . 6 Seeing Things in a Different Light . . . . . . . . . . . . . . . . 8 Red, Blue and Green, Oh My! . . . . . . . . . . . . . . . . . . 10 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Visit The Learning Site! www.harcourtschool.com Faster Than a Speeding Bullet Can you raise a window shade in the morning and then try to grab something in the room before light hits it? Of course, you can’t! Actually, no one can. Light is the fastest thing we know of—far faster than even a speeding bullet. In a vacuum, light travels just under 300,000 kilometers (186,

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