Question

how many strings of six uppercase enlgish letters are there .

A) if the letter can be repeated
B) if no letter can be repeated
C) that start with z if the letters can be repeated
D) That start with z and no letters can be repeated
E) That start and end with z and can be repeated

F that start with the letters NE in that order if the letters can be repeated
G) that start and end with the letters NE in that order and can be repeated

H) that start or end with the letters NE in that order if the letters can be repeated