Does anyone know what this is?

According to the number line, what is the distance between points a and b? v ++ + + + + -16 -14 -12 -10 -8 + 6 + 4 + -2 + 0 + 2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 o6 units o 7 units 12 units o 14 units

If i have one apple and give you the apple, how many apples do i have?

Using elimination, what is -4x+2y=-12 4x+8y=-24