What will be the difference between the compound interest and simple interest at the rate of 5% per annum on an amount of Rs 4000 at the end of 2 year?

The difference between the simple interest between the simple interest received from two different sources on ₹ 1500 for 3 years is ₹ 13.50. The difference between their rate of interest is - 

The simple interest on a sum of money is 4 / 9 of the principal and the number of years is equal to the rate percent per annum. The rate per annum is 

A sum of ₹ 400 amounts to ₹ 480 in 4 years. What will it amount to if the rate of interest is increased by 2 %? 

Out of ₹ 20, 000 Narendra gives some amount on loan at simple interest rate 8 % per annum and rest amount at simple interest rate 4 / 3 % per annum. At the end of year he earns ₹ 800. The amount given at 8 % rate will be –