Find the Future Value of Annuity... Joe and Susan are both 40 years old and hope to have enough money saved to retire by the time they’re 65. They deposit $6,000 each year into an account that pays 4% interest compounded annually.
Use the 'Future Value of Annuity' formula to find out the account balance in 25 years.
Then, find the total interest earned.

With: label the vertices and all the elements needed. find x

Water flows at a steady rate from a tap. its takes 40 seconds to fill a 4 litre watering can from the tap. the rate at which water flows from the tap is halved. complete: 4 litres into cm3

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters