Raja invested $Rs. 99000$ in $7 \frac{1}{2} \%$ stocks at $81 \frac{1}{2}$ (Brokerage: $Rs. 1$). Find out Raja's annual income from his investment. (in $Rs.$)

Find the income obtained by investing $Rs. 90000$ in $7 \frac{1}{2} \%$ stock at $112 \frac{1}{2}$ (in $Rs.$).

$A$ man bought $Rs. 20000$ of $5\%$ stock at $90$ and sold it when its price rose to $Rs. 93 \frac{3}{4}$. Find out his gain percent.

Anu invested $Rs.\, 32400$ in $8 \%$ stock at $90$. She sold $Rs.\, 18000$ stock when the price rose to $Rs.\, 95$ and the remaining stock at $Rs.\, 98$. She invested the total sale proceeds in $10 \%$ stock at $96 \frac{1}{2}$. Find the change in income of Anu (in $Rs.$).

Find the income on $12\%$ stock of $Rs.\, 60000$ purchased at $Rs.\, 110$. (in $Rs.$)

$12500$ shares, of par value $Rs.\, 20$ each, are purchased from Ram by Mohan at a price of $Rs.\, 25$ each. Find out the amount required to purchase the shares. If Mohan further sells the shares at a premium of $Rs.\, 11$ each, then find out his gain in the transaction. (in $Rs.$)