I need some help figuring #2 problem out.

The problem statement, all variables and given/known data

1. two charges of 6 microcoulombs and 10 microcoulombs are 10cm apart. Calculate their force of repulsion. Calculate the electric field midway between them.

2. For the charges in question 1 calculate the potential midway between them. Calculate the work to bring an electron from far away to midway between them.

So for the first question I used F= k |q1||q2|/r^2 for the second part of the first question i did E = k |q|/r^2

i calculated that the force would be 53.94N
As for the electric midway I calculate it to 3.6 x 10^6 N/c Although im not sure if i was supposed to add or subtract E1 and E2. So what i did is that i subtracted. But im not entirely sure if that is my correct answer

My work:
E1 = 8.99x 10^9 N*m^2/c^2 x |6 x10^-6 C|/(0.1m)^2

E1 = 5.39 x 10^6 N/c is my answer for E1

E2 = 8.99 x 10^9 N*m^2/c^2 x |10 x 10^-6C|/(0.1m)^2

E2 = 8.99 x 10 ^6 N/C

Then i did E = 8.99 x 10^6 N/C – 5.39 X 10^6 N/C
And I got 3.6 x 10^6 N/C however like i said before im not exactly sure if this was the correct approach to get the electric field midway

For the second question
I used this equation (U= k (q0)(q)/r —> k being 8.99 x10^9n.m^2/c^2 for part of the 1st question in question 2 that asks for potential midway and got an answer of U= 10.78 N M

however when they asked me for the work in question two i assumed I should have used -W=q0Ed
but i don’t know what numbers I would use for this equation. Would the correct way of going about it be
doing -W=(1.60 x 10^-19C)(8.99 x 10^6 N/C – 5.39 X 10^6 N/C)(0.1m) or is this wrong?

IF someone could please point me in the right direction and check if I’ve done these steps correctly it would be helpful. Thank you in advance.

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