A Norman window has the shape of a rectangle surmounted by a semicircle. (Thus the diameter of the semicircle is equal to the width of the rectangle.) If the perimeter of the window is 40 ft, find the value of x so that the greatest possible amount of light is admitted. (Give your answer correct to two decimal places.)

How much money does ron have left each month after his fixed expenses? ron graduated from college five years ago. he recently bought a house, but shares it with a housemate who pays him $800 a month for rent and utilities. ron is putting a budget worksheet together so he will have a better idea of where his money is going and where he can save. enlarge