3. Future value of annuity. (a) Lev will deposit $6,000 in an annuity each year (at the end of the year) for 10 years. How much will he have accumulated at the end of the 10th year? Assume 4 % interest. (b) Lev will deposit $3,000 in an annuity every six months (at the end of the period) for the next 10 years. This will be a total of 20 periods. Assume 2 % interest. How much will he have accumulated at the end of the 10th year? (c) Same information as (a), but assume payment is made at the beginning of each year. (d) Same information as (b), but assume payment is made at the beginning of the period