1. Forests stabilize _____and retain precipitation, thereby helping to prevent erosion and regulate the flow of streams.

2. During the decades after the United States Civil War, a host of technical advances made possible ______and uniformity of railroad service.

3. Stage producers Klaw and Erlanger were the first to eliminate arguments among leading performers _______in order of appearance, instead of prominence.

4. Pearl Sydenstricker Buck, _____ the Nobel Prize for Literature in 1938, is Best known for her novels about China

5. Astronomers estimate ______called the Pleiades in the constellation Taurus is 415 light-years away from Earth.

6. Digital recording has make _____ a significantly wider dynamic range, in recorded music.

7. The United States Constitution provides for a count of the population _____ a census, every ten years.

8. _____ are inert outside living cells, but within the appropriate cells they can replicate, causing viral diseases in the host organism.

9. Copper _____ used by humans and is second only to iron in its utility through the ages.

10. Grown widely in Iowa and Illinois, the soybean provides one of the world’s _____ sources of protein.

11. Thyme, _____ , yields a medicinal oil containing thymol.

12. _____ telescopes of the 1600’s magnified objects thirtythree times their original size.

13. The recent discovery of a novel by Harriet Wilson, published in 1859, _____ a landmark in Black American literature.

14. _____ time and labor, cartoonists generally draw the hands of their characters with only three fingers and a thumb.

15. _____ a bicameral, or two-chamber parliament.