Find the present values of the following annuities on December 3 1 , 2017, Use 6% interest. All payments are made on December 31 starting on December 31, 2018 a) Payments for 12 years starting at $20,000 and increasing by 4% every year b) Payments for 20 years starting at $30,000 and decreasing by 5% every year c) Payments for 10 years starting at $40,000 and increasing by 10% each year