A quality-control manager randomly selects 60 bottles of bleach that were filled on January 15 to assess the calibration of the filling machine. What is the population in the study?

Bottles of bleach produced in the plant on January 15.

Explanation:

Going by the question, the day the quality control accessment was done is just a single day of january 15 which will involve a sampling from the whole bottles of bleach produced on that day respectively. so the amount of bottles of bleach produced in the plant on January 15 will be the population in the study.