1.You signed a contract in which you will receive the following payments for the next five years: $10,000, $20,000, $30,000, $40,000, and $50,000 (from t = 1 to t = 5). You will then receive an annuity of $85,000 a year from Year 6 (t = 6) through the Year 15 (t = 15). The appropriate discount rate is 10 percent. How much is the contract worth now (at t = 0)? Please explain rationale of how to determine the contract's current worth with and without the use of Excel.

2.You purchased a house for $400,000, paid 20% of it as down payment and applied for a 30-year mortgage to finance the rest. The mortgage payment is scheduled at the end of each month. The 30-year fixed mortgage rate is 5% compounded monthly. How much is the monthly payment for this mortgage? Please explain rationale of how to determine the monthly mortgage payment with and without the use of Excel.