A uniform electric field with magnitude of is in the negative x direction. Point is at a coordinate of (0.40 m, 0.0 m) and point is at a coordinate of (0.70 m, 0.0 m). The potential between these points was measured to be 320 V. What is the value of the magnitude? Give the answer is units of V/m,

Now a point charge of -0.400 C is moved from point b to point a. What is the work done by the electric field on the point charge? Give the answer in mJ.