The force of the air's resistance to a certain car (in Newtons) as a function of the car's speed (km/h) is graphed. What is the approximate average rate at which the air's resistance increases, as the car accelerates from 50 km/h to 65 km/h?
graph
Choose 1
Choose 1

(Choice A)
A
111111 \text{N}Nstart text, N, end text per \text{km/h}km/hstart text, k, m, slash, h, end text

(Choice B)
B
11\dfrac1311
3
1
​
11, start fraction, 1, divided by, 3, end fraction \text{N}Nstart text, N, end text per \text{km/h}km/hstart text, k, m, slash, h, end text

(Choice C)
C
11\dfrac2311
3
2
​
11, start fraction, 2, divided by, 3, end fraction \text{N}Nstart text, N, end text per \text{km/h}km/hstart text, k, m, slash, h, end text

(Choice D)
D
121212 \text{N}Nstart text, N, end text per \text{km/h}km/h