Answer the following question based on the Compton's Encyclopedia reading: Which choice best describes the biggest impact of Jonas Salk's work with poliomyelitis?

Jonas Salk became a professor of medicine and the head of the Institute for Biological Studies.
Jonas Salk was celebrated for his work and awarded the Presidential Medal of Freedom.
Jonas Salk created a vaccine that has nearly eliminated the disease in the United States and many other developed countries.
Jonas Salk tested his vaccine on a large group of children and published his findings the following year.

The following question is based on your reading of a midsummer night’s dream by william shakespeare. what type of creature is bottom turned into? a. a goat. c. a mouse. b. an elf. d. a donkey.

Which word or phrase would smooth the transition between sentence 1 and sentence 2? o "in conclusion" o "for example" o "therefore" o"because"

(1) fire extended humans’ geographical boundaries by allowing them to travel into regions that were previously too cold to explore. (2) it also kept predators away, allowing early humans to sleep securely. (3) fire, in fact, has been a significant factor in human development and progress in many ways. (4) other obvious benefits of fire are its uses in cooking and in hunting. (5) probably even more important, however, is that learning to control fire allowed people to change the very rhythm of their lives. (6) before fire, the human daily cycle coincided with the rising and setting of the sun. (7) with fire, though, humans gained time to think and talk about the day’s events and to prepare strategies for coping with tomorrow. the sentence that expresses the main idea is: (type the number of the sentence. then click “go.”)