1. Select all of the true statements. A. Pi is the area of a circle of radius 1.
B. Pi is the area of a circle of diameter 1.
C. Pi is the circumference of a circle of radius 1.
D. Pi is the circumference of a circle of diameter 1.
E. Pi is the constant of proportionality relating the diameter of a circle to its circumference.
F. Pi is the constant of proportionality relating the radius of a circle to its area.

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.