Not sure how to figure this out

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?

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.

Tim knows the volume and base area of a wooden chest that is in the shape of a rectangular prism. if the volume is 524 cubic unit and the base area is 15 square unit, what is the height of the chest? 124 unit 1124 units 112 unit 1112 units