Help a-d

Two charges are placed on the x-axis with P qi at the origin and q2 a distance 0.20 m to the right of it. q1 = +4.00 uC and q2 = +9.00 uC a. (1) Sketch the total electric field vector at point P on the diagram to the right. (Just give general direction, e.g. to the left, diagonally upward, ....) b. (1) Where is the total electric field is zero? (Short qualitative answer, e.g. on the y-axis) c. (4) Find the point at which the total electric field is zero. d. (4) If the sign of the charge qi is negative, so that q1 = -4.00 JC and q2 = +9.00 JC, find the point at which the total electric field is zero