Please solve this

option a is correct.. divergence of (r cap/r^2) is 4*pi* dirac function not equal to zero,it is a special identity. do remember it...

see solution

option (b) is correct see the attachment

ans will be the 0 ,bcoz r(cap)/r² k divergene 0 ayega , aur tum dirac delta function k lya batao to volume intregral 0 ata hain ....so ans(b)