This is a homework problem involving direction of an electric field. The book is College Physics by Young & Geller, but the problem is online and not in the book.
A proton and an electron are separated as shown in the figure. (Proton to the north and electron to the south) Points A, B, and C lie on the perpendicular bisector of the line connecting these two charges.
First Question: Sketch the direction of the net electric field due to the two charges at point A (with tail at A)
Second Question: Sketch the direction of the net electric field due to the two charges at point B (with tail at B)
Third Question: sketch the direction of the net electric field due to the two charges at point C. (with tail at C)