A study is done to determine if Company A retains its workers longer than Company B. The populations are normally distributed having company A standard deviation of 1.2 and company B standard...

A study is done to determine if Company A retains its workers longer than Company B. The populations are normally distributed having company A standard deviation of 1.2 and company B standard deviation of 0.8. Company A samples 15 workers, and their average time with the company is five years. Company B samples 20 workers, and their average time with the company is 4.5 years. Test at 5% level of significance.