Ahmad want to buy a home in Ramallah $.$ The average price is $$150000.$ The bank asked him to have at least $30\%$ of the price before approving the loan. So Ahmad need to have $$50000\mathrm{.}1.$ Suppose Ahmad intend to buy the home in $5$ years,how much should he make monthly deposit so that he can reach $$50000?2.$ If Ahmad can afford to save only $$600$ monthly,a$.$ how many full monthly payments should he makes?b$.$What additional deposit is necessary $-$ after the last payment$-$ in order to reach the $50000$