If r = Xax + Yay + Zaz, the position vector of point x, y z and r follOwing is incorrect a Vr =rr c

If r = Xax + Yay + Zaz, the position vector of point (x, y. z) and r follOwing is incorrect? (a) Vr =r/r (c) V(del)2(r'r) 6 (b) V'r = 1 (d) V(del) X r =0