WeBWorK Standalone Renderer

Consider the vector field shown below.

Graph of a vector field that points down along the positive y-axis, up along the negative y-axis, to the right along the positive x-axis, and to the left along the negative x-axis, with vectors in the quadrants smoothly making the transition from vertical to horizontal vectors. Farther from the origin the vectors have larger magnitude.

(Note: For the vector field, vectors are shown with a dot at the tail of the vector.)

Let $C_1$ be the line from $(0, 0)$ to $(1, 1)$ , $C_2$ be the line from $(0, -1)$ to $(1, 0)$ , and $C_3$ be the semi-circle centered on the origin that goes from $(-1, 0)$ to $(1, 0)$ in a counterclockwise direction.

Is the line integral of the vector field along each of these curves positive, negative or zero?
Along $C_1$ , the integral is
Along $C_2$ , the integral is
Along $C_3$ , the integral is

You can earn partial credit on this problem.