Please, I need the development and correct answer for this problem. I would really appreciate it.

Question

An ion harvester is scouring deep space for isolated xenon (Xe+) ions. A xenon ion is singly ionized, and has a charge of +e. If the field meter reads 0.000000202 N/C, how far away is it from the ion?
________ m

I am using the formula:
r=sqrke/E, but I keep getting the wrong answer. Thank you.

Answer 1

E = k q/r^2

Answer 2

Can someone solve this please

Answer 3

E=ke/r²,
r=sqrt(ke/E) =
= sqrt(9•10⁹•1.6•10⁻¹⁹/2.02•10⁻⁷)=
=8.44•10⁻²m