Estimate the sum 59.6 + 51.4

You are a clerk at convenience store. a customer owes 11.69 for a bag of potatoes chips. she gives you a five dollar bill. how much change should the customer receive?

Your company will replace the asphalt roofs on all the buildings at the factory complex shown below. the buildings have flat roofs. you charge according to the total roof area. what is this area, in square yards?

What’s the answer? and how do i solve it ?