On a horizontal number line, the positive rational numbers are placed to the right of, to the left of, above or below zero, and the negative rational numbers are placed to the right of, to the left of, above or below zero.

The number line is oriented to the right. This means that the numbers get bigger as we travel to the right.

Since positive numbers (they don't need to be rational) are bigger than zero, and negative numbers are less than zero, the first lie to the right, and second to the left of zero.

correct answer:

b.(19,-2)