Help with this question plz

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

Mat bought a phone for $100. he has to pay $30 per mouth. if he has paid $640 in total, how many mouth has he had the phone?

The art class is planning to paint a mural on an outside wall. this figure is a scale drawing of the wall. width: 11 in length: 28 in unit rate: 1.5 ft per in. write the ratio of the area of the drawing to the area of the actual mural. write your answer as a unit rate. show that this unit rate is equal to the square of the unit rate 1.5 ft per in