can you explain it step by step?

36. Bob wants to establish a college fund for his son, who is 5 years old. Bob plans on senan a school that costs, in today's dollars, $25,000 annually. He expects college expenses to increase at a rate of 6%. He thinks that the money can be invested at a 7% rate of return. What amount does Bob need to contribute at the end of each year? His son will go to school for 4 years. a. $10,442 b. S10,132 c. $9,150 d. $8,152