qqp question1: How many ways can a 4-digit number be formed using the digits 3, 4, 4, 4, 5, 6, 6 and 7? question2: How many 3 digit numbers can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 if repetitions of digits are allowed?