Answer :
Final answer:
The plumb bob is the tool used to ensure level, straight, and plumb installations by establishing a true vertical reference line using gravity.
Explanation:
The plumb bob is the tool used to help ensure level, straight, and plumb installations. It works by utilizing gravity to establish a true vertical reference line. When a plumb bob is suspended from a fixed point, the string it hangs from provides a precise vertical line that can help align structures accurately.
Learn more about plumb bob here:
https://brainly.com/question/39655722