A loan of US$ 3,000 disbursed today is repaid in 5 installments commencing at end of year one. The second repayment is at the end of year two and is half as much again as the first installment and is 25% less than the third installment (due at the end of year four) . The fourth installment, due at the end of year five , is 15% more than the final installment. The final installment is due at the end of year seven and is 20% more than the first installment. The rate of interest is 15% p.a in year one, 17% p.a in year two , 19% p.a in years three and four , 12% in year five and 14% thereafter. Compute the amount of each installment.