Final answer:
The notion that a collar tie is a tension tie designed to prevent rafter separation is true. The concept of tension in a connector being the opposite forces is also true. However, the statement that high-voltage wires are wrapped in insulating material is false; they are bare and connected with insulators.
Step-by-step explanation:
The statement about a collar tie being a tension tie in the upper third of opposing gable rafters that is intended to resist rafter separation from the ridge beam is True. A collar tie's primary function is to prevent the rafters from spreading apart or sagging, and to help distribute the load of the roof evenly.
When we talk about tension in connectors such as strings, ropes, chains, or cables, the statement that tension is the result of opposite forces pulling each point of the connector apart in a direction parallel to the length of the connector is also True. The tension forces act towards the center of the connector at the ends.
Regarding the high-voltage wires connected to tall metal-frame towers, the assertion that these wires are wrapped in an insulating material is False. The high-voltage wires are not insulated; they're bare and held aloft by insulators, which prevent the current from flowing to the ground through the tower structure.