Respected tutors, I tried a lot but I can not solve the following question so please help me to solve it.

Use the model for stock prices described in section 11.5.3 in [2]. Suppose a stock has initial price 400$ and has volatility parameter equal to 9. Compute the probability that the stock price will be over 500$ after 8 years if the drift per year is equal to (a) 0$ (b) 5$ (c) 10$ (d) 20$.