The manager of a 70-unit apartment complex is trying to decide what rent to charge. Experience has shown that at a rent of $800 all of the units will be full. On average, one additional unit will be vacant for each $25 increase in rent. Answer parts (a) through (e) below. (a) Let x represent the number of $25 increases. Find an expression for the rent for each apartment. The rent for each apartment is given by (b) Find an expression for the number of apartments rented. The number of apartments rented is given by (c) Find an expression for the total revenue received from all rented apartments. R(x)= (d) What value of x leads to maximum revenue? The maximum revenue will happen when x = (Round to the nearest whole number as needed.) (e) What is the maximum revenue? The maximum revenue is $ (Round to the nearest whole number as needed.)