8. Governments usually build highways because it is difficult to exclude individuals who don't pay for the highways from using them. What type of failure is involved?

public good

Explanation:

Based on the information provided within the question it can be said that the type of failure that is involved is known as a public good. This term refers to a good that can benefit various individuals but is not excludable to anyone based on whether they can pay or not. Such as the highways being built, since they cannot prevent individuals who do not pay from using it.

you have to put the parentheses like this:

in fact, you have to perform the operation inside parentheses first, and then proceed in order: