A simply supported rolled steel joist 8 m long carries a uniformly distributed load over it span so
that the maximum bending stress is 75 N/mm². If the slope at the ends is 0.005 radian and the
value of E = 0.2 × 106
N/mm2
, the depth of the joist, is
(A) 200 mm
(B) 250 mm
(C) 300 mm
(D) 400 mm