An experimenter wanted to test the effects of cigarette smoking on rats. she infused the cages of 50 rats with cigarette smoke and the cages of another 50 rats with pure, clean air. the rats that received the clean air were the

Control group

Explanation:

A control group is a group of individuals in an experiment where the independent variable being tested (the exposition to cigarette smoke in this case) can't influence the results. This control group will be then compared to the experimental group (exposed to the smoke) to see the effect of the variable evaluated.

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yes i have all the correct answers

1. c 6. b. 11. c

2. a 7. d. 12. d

3. c 8. b. 13. c

4. d 9. c. 14. d

5. c 10. d. 15. a

16. d. 21. a

17. d.

18. a. 22-30 you must do on

19. d. your own

20. d.

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.