please solve this question using R language not python

Calculate the integral:

${\displaystyle \underset{0}{\overset{1}{}}}4\sqrt[\phantom{2}]{1-x^2}dx$

a$)$ Exactly $($with calculus methods$).$

b$)$ Using Monte Carlo integration with $U(0,1)$ density and $S=10,000$ values.

c$)$ Using Monte Carlo integration with $(2,2)$ density and $S=10,000$ values.