John has an investment opportunity that promises to pay him $18,500 in four years. He could earn a 8% annual return investing his money elsewhere. (FV ot $1, PV of $1. FVA ot $1, PVA of $1, FVAD of $1 and PVAD ot $) (Use appropriate factoris) from the tables provided.) What is the maximum amount he would be willing to invest in this opportunity