Calculate the NPV of a machine which is bought for $$8,000,$ sold at the end of year $4$ for $$5,000,$ and produces the following cash flows: year $1)+$$$700$; year $2)-$$$500$; year $3)+$$$1200$; year $4)+$$$2,400$; assume the cost of capital is $8\%.$

$$1,578\mathrm{.}97$

$$3,809\mathrm{.}78$

$$1,388\mathrm{.}70$

$$4,206\mathrm{.}51$