The temperature at a point (x, y) on a flat metal plate is given by T(x, y) = 25/(3 + x2 + y2), where T is measured in C and x, y in meters. Find the rate of change of temperature with respect to distance at the point (1, 2) in the x-direction and the y-direction. (a) the x-direction C/m (b) the y-direction "C/m