The greatest 4-digit numbers that can be formed using the digits 9, 0, 5 repeating any one digit twice is _______.
9950
9005
9550
9905
The greatest 4-digit number that can be formed using 7, 6, 0 and 5 without repeating the digits is ____.
What is the largest five digit number which can be formed using the digits 7, 8, 5, 4 and 9, if only one digit can be repeated twice?