Question

what is one of the key safety precautions that should be taken when working with hand and power tools at heights?
prop tools against the edge of the structure
use toe boards and guardrails to prevent tools from falling
throw tools to coworkers below
use any tool for any task

Explanation:

When working at heights with hand and power tools, toe boards and guardrails are safety features. Toe boards act as a barrier at the edge of a platform to stop tools from rolling off, and guardrails provide a physical barrier. Propping tools against the edge (risk of falling), throwing tools (risk of hitting someone), and using any tool for any task (improper use risks) are unsafe.

Answer:

Use toe boards and guardrails to prevent tools from falling