We know that population mean μ is 30 and population standard deviation σ is 5.
Further average or mean is computed for all sample means. So, the mean of sampling distribution of mean μxbar is calculated.
The property of sampling distribution is that mean of all possible sample means or mean of of sampling distribution of mean μxbar is equal to the population mean μ.
Add or subtract 360 degrees to find a coterminous angle. Since the questions wants you to find one between 0-360, you should subtract 360. 453-360=93 degrees