How can you use unit rates to make comparisons

Norma has an a-frame cabin. the back is shown below. how many square feet of paint will she need to cover the back of the cabin? explain how you found the answer.

Need on this one asap im almost done with this subject

Oscar and julie ashton are celebrating their 15th anniversary by having a reception hall. they have budgeted $4,500 for their reception. if the reception hall charges a $90 cleanup fee plus & 36 per person, find the greatest number of people that they may invite and still stay within their budget.