Define a variable. then write and solve an equation for each situation. the parker family drove a total of 180 miles on their road trip. this distance is 1.5 times the distance they drove on the first day. how many miles did the parker family drive on the first day? jose correctly answered 80% of the questions on a language arts quiz. if he answered 16 questions correctly, how many questions were on the language arts quiz?

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