A field is given as G = [25/(x2 + y2)](xax + yay). Find (a) a unit vector in the direction...

A field is given as G = [25/(x2 + y2)](xax + yay). Find (a) a unit vector in the direction of G at P(3,4, −2); (b) the angle between G and ax at P; (c) the value of the following double integral on the plane y = 7.