A fenced enclosure consists of a rectangle of length L and width 2R and a semicircle of radius R. The enclosure is to be built to have an area A of 2000 ft^2. The cost of the fence is $50 per foot for the curved portion and $40 per foot for the straight sides. Use the fminbnd function to determine with a resolution of 0.01 ft the values of R and L required to minimize the total cost of the fence. Also compute the minimum cost.