Yes, it is.
no
No.
The question cannot be answered because it is nonsensical. The difference between two rational numbers is very very rarely a whole number.
Yes. The rational numbers are a closed set with respect to subtraction.
Yes, that's true.
When you consider how many rational numbers there are, the difference between any two of them is hardly ever an integer. Examples: 5 - 4/5 = 41/5 5/6 - 2/3 = 1/6 3.274 - 1.368 = 1.906 All of the nine numbers in these examples are rational numbers.
No. sqrt(3) - sqrt(2) is irrational.
No, it is not true.
No. 5 and 2 are real numbers. Their difference, 3, is a rational number.
They will always be rational numbers.
They are always rational numbers.
Yes. This is the same as asking for one rational number to be subtracted from another; to do this each rational number is made into an equivalent rational number so that the two rational numbers have the same denominator, and then the numerators are subtracted which gives a rational number which may possibly be simplified.