Mr$.$ G$.$ has gone to Germany in order to work there and save some money. He planned to stay there $10$ years and estimated that he would earn $$4,800$ per year. But he has changed his plans and came to Turkey at the end of the $8^{th}$ year because he learned that he could serve his military obligations in a month by paying $$3,600$ to the government. After his military service, he returned to Germany and at the end of the $9^{th}$ year he met a girl in K$$ln$.$ They got engaged and he spent $$3,600$ for the engagement party. He spent another $$3,600$ for the wedding preparations at the end of the ${10}^{th}$ year. How much less will his savings be as compared to his plan at the end of year $10?i=\%12$

A car seller offers you a $0\%$ cost of payment plan for a car that has a price of $$15,000.$ But you have to make a down payment and an equal payments of $24$ months in order to get this car. The car seller can earn $1\%$ from his investments. What must the down payment be that you may get a $$1,000$ discount from the price of the car?