Generate a Monte Carlo algorithm for estimating the probability of a number less than −4 from a standard normal density. To do this, generate N = 10, 000 random normal variables with mean 0 and variance 1. Run this algorithm several times and see how much the estimate changes. Comment on the efficiency and stability of this estimate. Next, consider the use of Girsanov theorem to improve our estimate. Describe the transformation used. Have we improved our estimate?