please help me solve these 2 questions

a. A copper rod is cooled from 64 C to -25 C, and the length is held constant. The linear coefficient of thermal expansion of Cu is 17 x 10-6 0-1, and the elastic modulus of copper is 110 GPa. Determine the magnitude and type of stress developed on cooling from 64 C to -25 C. [2] b. To what temperature would 15.75 g of an iron specimen initially at 25C be raised if 1086.75 Joules of heat are supplied? (the specific heat capacity of iron is 0.46J/g C). [2]