A number with a square root is still a number. So the answer is all of them.
No. The square roots 8 are irrational, as are the square roots of most even numbers.
Numbers with square roots that are whole numbers
They are called real numbers. Negative square roots must be complex numbers.
No. Lots of square roots are not rational. Only the square roots of perfect square numbers are rational. So for example, the square root of 2 is not rational and the square root of 4 is rational.
No. The square roots of perfect squares are rational.
There are no real square roots of -256. But using complex numbers the square roots of -256 are 16i and -16i.
Negative numbers have no real square roots. In terms of complex numbers, the square roots of 43 are +j6.5574 (rounded) and -j6.5574 (rounded)
There are no following numbers!
Square roots of negative numbers ARE possible. I guess you haven't been introduced to "imaginary numbers" and the letter "i".
Rational numbers whose square roots are whole numbers are themselves whole numbers. They are called square numbers, e.g. 1, 4, 9, 16, 25 and so on.
Negative numbers do not have "real number" square roots.However, they will have two roots (when using imaginary numbers) as do other numbers, where a root including i(square root of -1) is positive or negative.
The square roots of a number are numbers and, as numbers, they are not capable of doing anything.