A point charge Q1=-2 microcoulomb is located at x=0, and a point charge Q2=+8 microcoulomb, is placed at x=-0.5 on the x axis of a cartesian coordinate system.The goal of this problem is to determine the electric field,at various points along the x axis.

Question

A point charge  Q1=-2 microcoulomb   is located at x=0, and a point charge Q2=+8 microcoulomb,    is placed at x=-0.5  on the x axis of a cartesian coordinate system.The goal of this problem is to determine the electric field,at various points along the x axis.

a)What is electric field  (in N/C) for  
  -55.0 m ? 
  
b)What is electric field  (in N/C) at  -0.22 m? 
c)What is  electric field (in N/C) at  92 m? 
d)At what point (apart from x=infinite), is the electric field zero ? Express your answer in meters.