Use Excel to answer this question

19 Your uncle has just announced that he is going to give you $15,000 per year at the end of each of the next 4 years. 20 21 a. (2 marks) 22 If the relevant interest rate is 7%, what is the value today of this promise? 23 24 b. (2 marks) 25 If the interest rate changes to 8%, what is the value today of this promise? 26 27 C. (2 marks) 28 Explain how interest rates influence the value of the promise in parts (a) and (b)