A heavy metal block is dragged along a rough horizontal surface at a constant speed of 20 ~km / hr . The coefficient of friction between the block and the surface is 0.6 . The block is made of a material whose specific heat is 0.1 cal / g - ^ C and absorbs 25 % of heat generated due to friction. If the block is dragged for 10 min , the rise in temperature of the block is about (g=10 ~m / s ^2 )