Question 1:
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Enter an integer: 3
three

Enter an integer: 0
zero

Enter an integer: 11
Error: function printdigit(), input must be between 0 and 9.

Question 2:
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Enter an integer: 10
ten

Enter an integer: 13
thirteen

Enter an integer: 21
Error: function print1x(), input must be between 10 and 19.

Question 3:
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Enter an integer: 10
ten

Enter an integer: 60
sixty

Enter an integer: 21
Error: function printX0(), input must be a multiple of 10 and less than 100.

Question 4:
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Enter an integer: 10
ten

Enter an integer: 60
sixty

Enter an integer: 21
twenty-one

Enter an integer: 45
forty-five

Enter an integer: 4
Error: function printtens(), input must be between 10 and 99.

Question 5:
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Enter an integer: 3
three

Enter an integer: 0
zero

Enter an integer: 10
ten

Enter an integer: 13
thirteen

Enter an integer: 60
sixty

Enter an integer: 45
forty-five

Enter an integer: 600
six hundred

Enter an integer: 105
one hundred and five

Enter an integer: 245
two hundred and forty-five

Enter an integer: 1050
Error: function printhundreds(), input must be between 0 and 999.