Please Help Me With This

Keiko is walking. The number of calories she has burned varies directly with the number of minutes she has walked. See the graph below.

How many minutes does Keiko walk per calorie burned?

What is the quotient of -3/8and-1/3?

The tuition costs, c, for a local community college are modeled by c(h) = 250 + 200h, where h represents the number of credit hours taken. the local state university has tuition costs, s, modeled by the function s(h) = 300 + 180h. 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.

Which of the following tables represents exponential functions?