I'm not sure about the formulas I need to calculate the following:

Value of a mixed streamFor each of the mixed streams of cash flows shown in the following table, determine the future value at the end of the final year if deposits are made into an account paying annual interest of 12%, assuming that no withdrawals are made during the period and that the deposits are made.

a. At the end of each year (i.e., the first deposit occurs 1 year from now)

b. At the beginning of each year (i.e., the first deposit occurs immediately)

Year Cash Flow Stream: A B C

1 900 30000 1200

2 1000 25000 1200

3 1200 20000 1000

4 10000 1900

5 500