Answer
The electric field halfway through the shell is zero in all three cases.
Work Step by Step
The electric field inside a conductor is always zero.
Therefore, the electric field halfway through the shell is zero in all three cases.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.