15. a) In a basement renovation, the contractor measured the length of a wall in a square room as 18 ft. 4 in. The width of the doorway is 3 ft. The contractor plans to place wood trim along the bottom of each wall. The trim costs $1.69/ft. What is the cost of the trim for the room, before taxes? b) The contractor uses the same trim around this window. 40 in. 26 in. Determine the cost of the trim for the window, before taxes. ​