Plz me get the right answer to these

Tony is charged $ 50 and additional $0.15 per miles for renting a car. a) represent the cost of renting a car with an equation,and the determine the cost if he drove it70 miles.b) what would be the cost of a car rental if the car was driven 250 miles? show work

What is the measure of ba (the minor arc) in the diagram below?

At school 460 of the students walk to school the number of students who take public transit is 20% of the number of students who walk. how many students take public transit