100 * 1000 : 60 : 60 = 27.77 m/s
I'll assume you're supposed to compute the line integral of
over the given path
. By the fundamental theorem of calculus,

so evaluating the integral is as simple as evaluting
at the endpoints of
. But first we need to determine
given its gradient.
We have

Differentiating with respect to
gives

and we end up with

for some constant
. Then the value of the line integral is
.
2,20 is the answer to the question.