:3. A list of numbers has an average of 10 and an SD of 3. A new
list is formed by adding 10 to the original list (for instance,
if the old list is 7,13, the new list is 7,13,10, and if the old
list is 4,10, the new list is 4,10,10).  Comparing the new list
to the old list, we can say that

 a.  The average and SD both go up
 b.  The average goes up and the SD goes down
 c.  The average is still 10, but the SD of the new list is  
         bigger
 d.  Both the average and SD remain the same
 e.  The average remains 10, but the SD of the new list is   
         smaller