The temperature at a point (x, y, z) is given by T(x, y, z) = 400e-x-5-2-2 where T is measured in C and x, y, z in meters. (a) Find the rate of change of temperature (in C/m) at the point P(2, -1, 4) in the direction toward the point (3,-5, 6). C/m (b) In which direction does the temperature increase fastest at P? (c) Find the maximum rate of increase at P.