1. The Louisiana Territory, an area …. the size of France, was bought by the United States from France for $15,000,000 in 1803.
2. Despite claims that filters and low-tar tobaco make smoking somewhat safer, in fact they only marginally reduce, …. eliminate the hazards.
3. ….. many of the designs for the new capital were considered lost forever, Benjamin Banneker helped reproduce the original plans.
4. Few natural elements exist in …. that they are rarely seen in their natural environments.
5. Generally speaking, every person …. the potential to be a teacher, to some extent.
6. …… business, a merger is a combination of two or more corporations under one management.
7. ….. of commodities by air began in the 1920s at the same as airmail service.
8. Jan Malzeliger’s invention, the shoe-lasting machine, …. production but it also cut the cost of shoe production by half.
9. It can sometimes …. a home.
10. Jellyfish are probably ….. on Earth.
11. In the United States …. is the most concentrated is New Orleans.
12. A log grabber has a long arm ….., which stretches out to pick up logs.
13. A home computer …. an opportunity for convenient and efficient work at home.
14. Eli Whitney’s milling machine remained unchanged for a century and a half because ….. was so efficient.
15. Some of the rainwater from clouds evaporates before ….
16. Once an offending allergen has been identified …. tests, it is possible for the doctor to give specific desensitizing injections.
17. Sometimes ….. wears people out and is worse than the lack of sleep itself.
18. Although dissimilar in almost every other respect, birds and insects have both evolved efficient .... capabilities.
19. The wheel, ..... has remained important for 4,000 years, is one of mankind’s first inventions.
20. ...... children master the basics, advanced development becomes easier.