Derivative

Q. If $f\left(x\right)=1+x+\frac{x^2}{2}+....+\frac{x^{200}}{200}$
, then f '(1) is equal to

1. $\frac{1}{200}$
2. 200
3. 100
4. \N

Q. If $f\left(x\right)=x^n$

and f '(1) = 15, then the value of n is

Q. If for the function $f\left(x\right)={\mathrm{kx}}^2+7x-19,f\text{'}\left(5\right)=57,$then the value of k is