There are 360 degrees so divide 360 by 20 and get 18 degrees
The bottom rectangle is 52 ft by 27 ft.
The top rectangle is 30 ft by 17 ft (calculated as 57 ft - 27 ft - 13 ft = 17 ft).
The connector rectangle is 13 ft by 9 ft (calculated as 30 ft - 21 ft = 9 ft).
total area = 52 ft * 27 ft + 30 ft * 17 ft + 13 ft * 9 ft
total area = 1404 ft^2 + 510 ft^2 + 117 ft^2
total area = 2031 ft^2
weight = 2031 ft^2 * 12 lb/ft^2
weight = 24,372 lb