Which of the following are true?

a. There is no such thing as PV pf a perpetuity

b. The formula of PV of an annuity would give us the value at the end of the year 4 for an annuity with a first payment that occurs at end of year 5

c. The time for a lender $1000 for one year at a rate of 8% compounded annually would include a negative $1080 at the end of year 1

d. The compounding process subtracts the interest part from the PV