How many 4-character license plates are possible with 2 letters from the alphabet followed by 2 digits, if repetitions are allowed? If repetitions are not allowed?

could someone please help me with the formula, I don't understand it yet

would this be the answer?

If repetition is allowed it would be
26 * 26 * 10 * 10 = 67600

If repetition is not allowed it would be
26 * 25 * 10 * 9 = 58500