The equation of a road is:
ax^2 from A to B
R(x) {
bx + c from B to C
B is 1000 feet horizontally from A and 100 feet higher. Since the road is smooth, R'(x) is continuous. What is the value of B?

I think it involves some differentiation.. but I don't really know what to do. The options for answers are:

a) .2
b) .02
c) .002
d) .0002
e) .00002



??????????????????????????????????????????????????