You must choose among a set of projects $($each project is unique and cannot be repeated$).$ The net present value of the future stream of returns, as well as the capital requirements for the next three years are given below. The available capital funds for the next three years are: $$7,000$ for Year $1,$ $$5,000$ for Year $2,$ and $$6,000$ for Year $3.$

Project $($i$),$ Net present value $($$$),$Capital requirements for Year $1($$$),$ Capital requirements for Year $2($$$),$ Capital requirements for Year $3($$$)$

Warehouse expansion $(1)6,0002,5003,5003,500$

Basic research $(2)8,0005,0001,0004,000$

New equipment $(3)3,0001,000500900$

Advertising campaign $(4)4,0002,0001,5001,800$

Let Xi $=1$ if choose project i $($ i $=1,2,3,4),$ Xi $=0$ if not.

Write down your objective function $($include min$/$max with the equation$)$ and constraints below, include descriptions$/$explanations$/$calculations on the right. Delete$/$add rows as needed.