Rational Numbers

Consider the following statements : 1. There is a finite a number of rational numbers between any two rational numbers. 2. There is an infinite number of rational numbers between any two rational numbers. 3. There is a finite number of irrational numbers between any two rational numbers. Which of the above statements is/are correct?

Rational number as recurring / terminating

Cube of a rational number

The negative of a negative rational number is always a ________ rational number

Reciprocal of every rational number is a rational number.

The negative of a negative rational number is a positive rational number

0 is a rational number. The rational number just next to it is-

If -1 is obtained on doubling a rational number then the rational number is