① Rational number can be an integer or a fraction ② Rational number can be a positive number or a negative number.
Integer can be positive or negative. The score can be positive or negative.
A 1 B 2 C 3 D 4
2.a and B are rational numbers, and the positions of their corresponding points on the number axis are shown in the following figure:
Put a, -A, b and -B () in descending order.
a-B