A metal rod of cross sectional area `1.0cm^(2)` is being heated at one end. At one time , the temperature gradient is `5.0^(@)C cm^(-1)` at cross section A and is `2.5^(@)Ccm^(-1)` at cross section B. calculate the rate at which the temperature is increasing in the part AB of the rod. The heat capacity of the part AB`=0.40J^(@)C^(-1)` , thermal conductivity of the material of the rod. `K=200Wm^(-1)C^(-1)` . Neglect any loss of heat to the atmosphere.