Company C has a capital allocation of $600,000. The following five projects are available. Which projects should the company invest in to maximize IRR, and what is the corresponding NPV and total investment?

Project	Investment ($000)	NPV ($000)	IRR (%)
1	250	55	18.0
2	100	15	11.0
3	200	40	14.0
4	150	25	12.0
5	300	65	17.5

Requirements:

1. Stay within the $600,000 budget.
2. Maximize IRR.
3. Calculate the combined NPV of selected projects.
4. Provide the total investment amount.