Is a vague pronoun a word that takes the place of a noun?

A vague pronoun is a pronoun that is unspecific like they

Explanation:

the economic activity signified in that scenario is a. production

in general, market production makes reference to the elaboration of a product or service which is destinated for economic purposes (to be sold) at money-price in a market. such product or service has to be principally tradable for money.

there is no money exchange involved in distribution, generalized reciprocity or balanced reciprocity.

at hatfield elementary school, there are 504 students in 7 classes. each class has the same number of students. what is a good estimate of the number of students in each class?