Which equation could be used to solve the problem?
the jensens drove 400 miles in 8 hours.
how many miles per hour did they drive (m)?
a. m = 8 hours ÷ 400 miles
b. m = 400 miles • 8 hours
c. m = 400 miles ÷ 8 hours
d. m = 400 miles + 8 hours

Researchers are conducting experiments to determine the role of alcohol in the development of depression. after the study is complete, they determine that the relative risk of developing depression is 1.55 with a 95 % ci of 1.2 -1.9. each group is then divided into nonsmokers and smokers. the relative risk for the nonsmokers is 1.12 with a 95% ci of 0.87-1.37. the relative risk for the smokers is 1.7 with a 95 % cl of 1.5-1.9. what type of bias may affect this study? a. procedure bias b. recall bias c. selection bias d. confounding e. lead-time bias