A timbre beam 100mm wide and 200mm deep is to be reinforced by bolting on two steel flitches each 150mm by 12.5mm in section. Calculate the moment of resistance in the following cases: (a) flitches attached symmetrically at the top and bottom (b) flitches attached symmetrically at the sides. Allowable stress in timbre is 6N/mm2. What is the maximum stress in the steel in each case? Take Es=200000N/mm2 and Et=10000N/mm2.