no
Yes, it is.
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.
Such a sum is always rational.