Answer from cs61c-aj (Kevin Li 15855812) for Question 2
b and c. When a block being released is next to a block that is a free block. free will combine the two causing the number of free block to remain the same. c occurs when a block being released is in the middle of two free blocks. free will combine all three blocks in to one. Originally there are two free blocks now there is one, and so therefore the number of free blocks is reduced by 1. It is not a because it doesn't always increase the number of free blocks and it is not d because the most it can combine is when it combines from the two sides and that only reduces the number of free blocks by 1.