The compound interest (in ₹) on ₹ $6250$ at $12 \%$ per annum for $1$ year,compounded half-yearly is

$A$ man gets a simple interest of $Rs. 1000$ on a certain principal at the rate of $5$ $p.c.p.a.$ in $4$ years. What compound interest (in $Rs.$) will the man get on twice the principal in two years at the same rate?

$A$ person takes a loan of ₹ $10,000$ at an interest rate of $10 \%$ compounded annually for a period of $4$ years. How much interest (in ₹) does he have to pay?

Amit invested an amount of $Rs. 25000$ in a fixed deposit at a compound interest rate of $8 \%$ per annum for $2$ years. What amount (in $Rs.$) will Amit receive at the end of the period?

Find the difference between $C.I.$ and $S.I.$ on $Rs. 15000$ at $3 \%$ per annum for $3$ years.

₹ $6,100$ was partly invested in Scheme $A$ at $10 \%$ p.a. compound interest (compounded annually) for $2$ years and partly in Scheme $B$ at $10 \%$ p.a. simple interest for $4$ years. Both the schemes pay equal interests. How much was invested (in ₹) in Scheme $A$?