If the present value of $143 is $129, what is the discount factor?

If that $143 is received in year 5, what is the interest rate?

what is the PV of $200 received in:

a. Year 8 (at a discount rate of 4%)?

b. Year 8 (at a discount rate of 16%)?

c. Year 13 (at a diacount rate of 28%)?

d. Each of years 1 through 3 ( at a discount rate of 15%)?