Question

what would happen if telephone wires were pulled tight between the poles during construction

Answer 1

If they were constructed during summer loosely then it would expand due to heat.
Therefore if they were constructed during summer then the must be constructed tightly to avoid collapse.
If they were constructed during winter then they must be constructed loosely as due to cold it would tend to contract. If they were constructed tightly then it would again collapse.

Answer 2

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