My co-worker erich is very odd. he only likes numbers that are divisible by 5. how many different last digits are possible in numbers that erich likes?

Solution:

A number is divisible by 5 if and only if it ends in 0 or 5, so there are only 2 possible last digits.

the battle of gettysburg is considered the "high water mark" of the confederacy because it marked the greatest advance of the confederate forces against the union.