It is known that the population standard deviation of recovery time from a cold is 1.8 days when treated with multivitamin tablets, and the population standard deviation of recovery time from a cold is 1.5 days when treated with placebo tablets. It is also known that both populations are approximately normally distributed. The researchers claim that the mean recovery time, u1, of the patients treated with multivitamin is not equal to the mean recovery time u2, of the patients who are treated with placebo tablets. At the 0.01 level of significance, is there enough evidence to support this claim? Perform a two-tailed test. Then complete the parts below.
Carry your intermediate computations to at least three decimal places.