A pre-tensioned concrete member of section 200 mm x 250 mm contains tendons of area 500 mm^{2} at centre of gravity of the section. The prestress in the tendons is 1000 N/mm^{2}. Assuming modular ratio as 10, the stress (N/mm^{2}) in concrete is

A river 5 m deep consists of a sand bed with saturated unit weight of 20 kN/m^{3} . v_{w} = 9.81 kN/m^{3}. The effective vertical stress at 5 m from the top of sand bed is

The effective width of a reinforced concrete T beam flange under compression, according to IS : 456-1978, given I_{0} is the distance between the adjacent zero moment points, b is the breadth of the rib and D is the thickness of the flange, is