Can someone help me with this question?

Geometry answer picture question pls . reason and statements

Samantha swam upstream for some distance in one hour. she then swam downstream the same river for the same distance in only 12 minutes. if the river flows at 4 mph, how fast can samantha swim in still water?

How many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.