I think below problem in the variation quiz has wrong answer.
Going back to the combination lock example from the lecture, imagine the correct code consisted of a single 4-letter word. However, this time the passcode only consists of the letters of “password”. How many possible passcodes are there?
I think Correct option is 8^4. The word 'Password' contains eight letters and correct code consisted of single 4-letters. thus it may be 8^4.
Correct me if I am wrong.