There are 27 pennies on one page of a pan balance and 18 pennies on the other. to make the pans balance, hillary thinks 5 pennies should be added to the higher pan, sean thinks 8 pennies should be added, and rachel thinks 9 pennies should be added. use the equation 27 = 18 + p to determine who is correct

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