9. A motorboat heads upstream a certain distance and returns to its starting point. The trip up and back takes 10 hours. The current is running at 2 miles per hour (mph). If the motorboat maintained a constant
speed of 8 mph relative to the water, what is the total distance of the trip?

Concerned about campus safety, college officials want to estimate the percentage of students who carry a gun, knife, or other such weapon. how many randomly selected students must be surveyed in order to be 95 % confident that the sample percentage has a margin of error of two percentage points?