ST Manufacturing Ltd is evaluating an investment of a machine that cost $200,000. With the new machine, the firms annual cash inflow will increase by $40,000 every year for the next 7 years. At the end of the 7 years, the company will scrap the machine and do not expect to receive any salvage value for it. Given the firms cost of capital is 6%, calculate the internal rate of return (IRR) of this investment. Should the firm purchase the machine? Give your reason(s)