Hayden has $200 and saves $40 more each week. however, every week she spends $10 on dutch bros coffee. if she wants to have $800 to buy a new computer, how long will it take for her to save this amount?

I’m on question 7 it says a covered water tank is in the shape of a cylinder the tank has a 28 inch diameter and a height of 66 inches to the nearest square inch what is the surface area of the water tank