Question

Old ones ran multiple shifts means

Answer 1

Answer:

It means that the old factories had two or more recurring time periods in which different groups of workers did the same job one after the other.

Explanation:

I'll give you an example. Every building has security gaurds. But it is not possible that only one gaurd would work day and night. So, in this case, during the day, there is a security gaurd, and during the night there is another security gaurd. This means that they have day shift and night shift. Similarly, workers in the factories had shifts to accomodate the increasing demands.

Hope this helps!