L x W = SQ FT
10 ( L ) x 50 ( W ) = 500 SQ FT
L x Avg. W = SQ FT
Avg. W = ( 40 + 45 + 40 ) / 3 = 42
50 ( L ) x 42 ( Avg. W ) = 2100 SQ FT
( B x H ) / 2 = SQ FT
50 ( B ) x 25 ( H ) = 1250 / 2 = 625 SQ FT
3.14 x R x R = SQ FT
3.14 x 18 ( R ) x 18 ( R ) = 1017 SQ FT
Area A is 10 x 10 = 100 SQ FT
Area B is 15 x 20 = 300 SQ FT
Area C is 12 x b20 / 2 = 120 SQ FT
Total Area = 520 SQ FT