The surface area, sa, of a right circular cone is sa=pi r squared + pi r s, where r is the radius of the circular cone and s is the slant height. using rounding to the nearest whole number, which of the following is an estimate of the volume of a cylinder with a radius of 4.42 meters and a slant height of 2.61 meters?
a: 84
b: 111
c: 125
d: 150

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