A large bakery makes cakes in two shifts: shift A and shift B. Suppose that, on average, cakes from shift A weigh
7.4 kg with a standard deviation of 0.2 kg. For shift B, the mean and standard deviation are 7.0 kg and 0.1 kg,
respectively.
Every day, the bakery takes an SRS of 25 cakes from each shift. They calculate the mean weight for each sample,
then look at the difference (A - B) between the sample means.
What are the mean and standard deviation (in kilograms) of the sampling distribution of CA - TB?