A sum becomes double in 10 years, then what is the annual rate of simple interest?

Sumit has Rs. 90000 with him. He purchases three items A, B, and C for Rs. 15000, Rs. 13000, and Rs. 35000 respectively and puts the remaining money in a bank deposit that pays compound interest @15% per annum. After 2 years, he sells off the three items at 80% of their original price and also withdraws his entire money from the bank by closing the account. What is the total change in his asset?

A certain sum is lent at a certain rate of compound interest. It grows to 1.44 times its value in 2 years. If the same sum is lent at simple interest at the same rate, in how many years would it double itself?

An amount doubles itself at compound interest in 5 years. How many years will it take to make the amount 16 times itself ?

The difference between compound and simple interests on a certain sum of money at the interest rate of $10\%$ per annum for $1\frac{1}{2}$ years is $₹183$, when the interest is compounded semi-annually, then the sum of money is :

In 4 years, an amount of ₹ 6,000 becomes ₹ 8,000 at a certain rate of simple interest. In what time at the same simple interest rate, will an amount of ₹ 525 become ₹ 700?