Answer:
He originally invested $3,068.04
Explanation:
This question is basically asking for Present value (PV) of one-time cashflow.
Present value formula ; PV =

$14,300 received 20 years from today is a future value so that will be your FV.
FV= 14300
t = 20 years
rate ;r = 8% or 0.08 as a decimal
PV =

PV=14,300 /4.66095714
PV= 3,068.03937
Therefore he originally invested $3,068.04