1. Find the ordinary and exact interest on 2000 for 820 days at 4% simple interest.
2. Mr. Ali received 12000 in a bank charging 2% discount rate. How much would he pay at the end of 90 months?
3. Find the interest and accumulated amount 20100 for 16 years at 3% simple interest.
4. If a principle of 15000 earns interest of 800 in 15 years and 7 months, what interest rate is in effect?
5. Find the interest and final amount on 7500 at 3% simple interest for 18 months.