In Cartesian coordinates, the temperature of a fluid is given by T=1005z(where z is in meters, and T is in K ).a) Find gradTb) If the velocity is given by v=ye0ey0e(where is a positive constant, and v has units of ms), evaluate DTDt and give a physical interpretation of the result.c) If the velocity is given by v=0ex0eye, evaluate DTDt and give a physical interpretation of the result.d) For the velocity given in part (b), determine the value of A(v*n)dA where A is the surface of a sphere centered at the position (1,1,0), with radius 1.(Hint: Use the GaussDivergence Theorem.)