I've been working on a couple of practice questions for my stochastic class, but am stuck on this one. THESE ARE NOT HOMEWORK OR FOR A GRADE. They...

Hi! I've been working on a couple of practice questions for my stochastic class, but am stuck on this one. THESE ARE NOT HOMEWORK OR FOR A GRADE. They are just practice problems. Could anyone possibly send me a step by step solution so I may understand how to do similar problems?