Any integer divided by a non-zero integer is rational.
Yes.
Because that is how a rational number is defined!
Because that is how a rational number is defined!
Yes, always. That is the definition of a rational number.
Yes, by definition.
I had this name question for homework :| no
No.
The quotient of two nonzero integers is the definition of a rational number. There are nonzero numbers other than integers (imaginary, rational non-integers) that the quotient of would not be a rational number. If the two nonzero numbers are rational themselves, then the quotient will be rational. (For example, 4 divided by 2 is 2: all of those numbers are rational).
No.
Usually not.
Yes.