(a) What conclusions can you draw about changes in the mean and the standard deviation when the same number is added to or subtracted from each piece of data in a set of data? 

(b) How will the mean and standard deviation of the numbers 8, 9, 10, 11, 12, 13, 14 differ from the mean and standard deviation of the numbers 648, 649, 650, 651, 652, 653, 654? Determine the mean and standard deviation of both sets of numbers.

Where appropriate, round standard deviations to the nearest hundredth.