How many numbers of four digits can be formed with the digits 1,2,4,5,7 no digit being repeated?

How many numbers of 3 digits can be formed with the digits 1,2,3,4,5 when digits may be repeated?

How many numbers of four digits can be formed with the digits 1,2,3,4,5 if the digits can be repeated in the same number?

The number of 3 digits can be formed with the digits 1,2,3,4,5 when digits may be repeated is

How many even numbers of four digits can be formed with the digits 0,1,2,3,4,5 and 6 no digit being used more than once?

How many numbers of four digits can be formed with the digits 1,2,3,4, and 5? (if repetition of digits is not allowed).