yes
Yes.
yes
It must be a generalised rational number. Otherwise, if you select a rational number to multiply, then you will only prove it for that number.
Yes. Any rational number divided by another rational number is also rational.
No.
Yes.
irrational
Because it can be expressed as a ratio of integers. 105/10
irrational
It is a rational number. It can be written as a fraction.
yes
Is 12.05 a rational number or irrational number?
1.96 is a rational number
It is a rational number, as it can be written as a fraction.
Yes, the sum is always rational.
There is no such thing as a number that is both rational and irrational. By definition, every number is either rational or irrational.