18. The extra band of metal across the back of a(n) stiffens the saw to help prevent
bending and inaccurate cuts.

Backsaw.

Explanation:

A backsaw can be defined as a short handsaw with a rectangular blade and a reinforced metal rib (stiffening rib) along its back so as to make the blade perfectly straight and allow for better control. Also, the reinforced metal rib (stiffening rib) helps to give a more precise cut better than other types of handsaw and as a result of this, it is mostly used in woodworking such as cutting tenons, mitres, or dovetails.

Hence, the extra band of metal across the back of a backsaw stiffens the saw to help prevent bending and inaccurate cuts.

the warning light flashes for a second or two when the engine starts. if it stays on, there's must be something wrong with the coolant. you should never dare to continue driving when the light is on. pull over as soon as possible and shut the engine off.

hope this is what you're talking about