In order to estimate the ratio of white to black students in his college, a professor determines the proportion of whites and blacks in his class. The students in the professor's class are called .

sample

Explanation:

A sample are said to be set of data that are collected and that are usually selected or not selected hrough various means or procedures from a given and defined population.

sample can also be referred to as a defined group of people who actively takes part in an experiment or investigation. The people who involved in the experience(takes part) are called participants

A sample is of different types and kinds some are biased and unbiased sample, random and non random sample and others.

good question. i'll be looking into that. (this is a joke sir)