Chapter 1, Problem 1.9P

A field is given as $G=[25/\left(x^2+y^2\right)]\left(x{a}_x+y{a}_y\right)$. Find (a) a unit vector in the direction of G at P(3, 4, —2); (b) the angle between G and a_x at P; (c) the value of the following double integral on the plane y = 7. ${\int }_0^4{\int }_0^{2}G.a_{y}dzdx$