 Hello, I am welcome to the session. I am Deepika here. Let's discuss the question which says A and B are two events such that probability of A is not equal to 0. Find probability of B upon A. If A is a subset of B, A intersection B is equal to 5. Now we know that the conditional probability of an event E given the occurrence of the event F is given by probability of E upon F is equal to probability of E intersection F upon probability of F provided probability of F is not equal to 0. So this is a key idea behind that question. We will take the help of this key idea to solve the above question. So let's start the solution. Now according to the question A and B are two events such that probability of A is not equal to 0. We have to find probability of B upon A if A is a subset of B. So in part one if A is a subset of B this implies A intersection B is equal to A. So according to our key idea we have probability of B upon A is equal to probability of B intersection A upon probability of A provided probability of A is not equal to 0. Now here we are given probability of A is not equal to 0. Now probability of V intersection A is equal to probability of A as A intersection B is equal to A. So probability of B upon A is equal to probability of A upon probability of A and this is equal to 1. So the answer for part one is 1. Now in part two we have to find probability of B upon A if A intersection B is equal to 5. Now A intersection B is equal to 5 implies probability of A intersection B is equal to 0. Therefore probability of B upon A which is given by probability of B intersection A over probability of A is equal to 0 upon probability of A which is again equal to 0. Hence the answer for this part is 0. So this completes our session. I hope the solution is clear to you. Bye and have a nice day.