Need answers asap please

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

What is the average rate of change for this function for the interval from x=2 to x=4 ?

7. the area of the playing surface at the olympic stadium in beijing isof a hectare. what area will it occupy on a plan drawn to a scaleof 1: 500?