1.sigma r^2(r+1)/r!

   splitting into partial fractions and writing sigma1/r!=e(r=0 to infinity),1/r-1!=e(r=1 to infinity) &so on,we get ans as 7e

 

2.sigmar(r+1)/r!

   following similar method,we get3e

 

   if ans are correct,please rate me

Thats what i mean

1/x^2=x^-2

Q remains same.But final C becomes C/3 (as d is increased)

 so,work done=finalenergy-initial energy

                    =Q^2/2(3/C-1/C)

                    =Q^2/C=CV^2

Since it is connected to battery,v remains constant.

so,E=1/2v^2C=1/2V^2eA/x

    Rate is proportional to1/x^2