3. Find the present values of the following annuities on December 31, 2020 at 6% interest. In each case payments start in 2021.

a. Continuous payments over 10 years starting at a rate of $5,000/year. The rate increases by $5,000/year every year.

b. Monthly payments over 15 years starting at a rate of $36,000/year. The rate decreases by $2,400/year every year

c. Quarterly payments over 8 years starting at a rate of $5,000/year. The rate increases by 3% every year.

d. Continuous over 12 years starting at a rate of $30,000/year. The rate decreases by 10% every year.

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