Calculate the value of the following at the end of month 19.

a) $150 every three quarters forever, starting at month 13, interest rate is 2% per quarter.

b) $90 per month, starting at quarter 7, ending at year 24, interest rate is 20% compounded quarterly.

c) Payment every two months, starting at the beginning of quarter 6, ending at the year 6, first payment is $180 and grows at 3% per month, interest rate is 18% compounded continuously.

d) $200 every three quarters forever, starting at month 5 and grow at 2% per quarter, interest rate is 16% compounded semi-annually.