What is the internal rate of return (IRR) for an investment costing $450,000 that is expected to produce cash flow of $200,000 at the end of year 1, $150,000 at the end of year 2 and $200,000 at the end of year 3. Express your answer to the closest half percent only. (eg 4% or 4.5% otherwise moodle will mark you incorrectly)