Answer with Explanation:
We are given that
[tex]E=4500 N/C[/tex]
[tex]q=-5.5\times 10^{-9} C[/tex]
a.x=-0.2 m
[tex]E'=\frac{Kq}{r^2}=\frac{9\times 10^9\times 5.5\times 10^{-9}}{(0.2)^2}=1237.5 N[/tex]
Where [tex]k=9\times 10^9[/tex]
Net electric field=E+E'=4500+1237.5=5737.5 N/C
b.x=0.20 m
Net electric field=E-E'=4500-1237.5=3262.5 N/C
c.y=0.20 m
E=1237.5 N/C
Net electric field=[tex]\sqrt{E^2+E'^2}=\sqrt{(4500)^2+(1237.5)^2}=4667.05 N/C[/tex]