Find the income by investing $Rs. 81000$ in $9 \%$ stock at $135$. (in $Rs.$)

$A$ man invests $Rs. 27600$ in $4 \%$ stock at $92$. He sold $Rs. 20000$ stock when the price rose to $Rs. 96$,and sold the remaining stock when the market value fell to $Rs. 90$. How much does he gain or loss in the transaction?

$A$ person buys $9 \frac{1}{2} \%$ stock of $Rs.\, 72000$ at $144$. Find his annual income (in $Rs.$).

The shares of a company of par value $Rs. 10$ each,are available at $20\%$ premium. Find out the amount paid by the buyer who wants to buy $2500$ shares. What would be the gain of the buyer if he sells those shares at the rate of $Rs. 20$ per share? (in $Rs.$)

Find the investment required to purchase $Rs.\, 125000$ of $8 \%$ stock at $92$. (in $Rs.$)

$A$ man invested $Rs. 50490$ in $5\%$ stock at $99$ and sold it when the price rose to $Rs. 102$. He invested the sale proceeds in $8\%$ stock at $96$. Find out the change in the man's income (Brokerage: $Rs. 3$).