Please solve the problem step by step.

21) The rate of a continuous money flow starts at $1000 and decreases exponentially at 4% per year for

10 years. Find the present value if interest is earned at 2% compounded continuously.

A) $13,701.98 B) $25,813.53 C) $30,368.65 D) $7519.81

22) A money market fund has a continuous flow of money at a rate of f(x) = 0.5x for 10 years. Find the

final amount if interest is earned at 8% compounded continuously.

A) $66.50 B) $158.25 C) $314.50 D) $33.25

23) The rate of a continuous money flow starts at $500 and increases exponentially at 4% per year for

10 years. Find the final amount if interest is earned at 8% compounded continuously.

A) $13,682.20 B) $9171.45 C) $46,467.07 D) $41,501.46