S I = 1/2 .41.30 = 615 ( m 2 )
S I I = 1/2 (30 + 20).50 = 1250 ( m 2 )
S I I I = 1/2 .20.19 = 190 ( m 2 )
S I V = 1/2 .19.56 = 532 ( m 2 )
S V = 1/2 (19+16).34 = 595 ( m 2 )
S V I = 1/2 .16.20 = 160 ( m 2 )
S = S I + S I I + S I I I + S I V + S V + S V I ( m 2 )
= (615 + 1250 + 190 + 532 + 595 + 160) = 3342 ( m 2 ).