You have the option to either invest now or invest in two years in a project with the following cash flows
Time 0 1 2 3 4 5 6
Now -25 4 6 10 5 8 9
In two years -30 10 10 10 10
If the cost of capital is 8 percent
Invest now because NPV is higher
Invest in 2 years
Neither
Invest now because NPV of waiting is negative