Which of the following is the term used to describe costs which change day to day, week to week and month to month based on business activities?

Variable costs

Explanation:

Variable costs is the term that describes business costs that vary with the production level. An increase in output increases the variable costs. Variable costs are progressive and increase or decrease with the production volume.

Examples of variable costs include raw material and distribution costs. Variable costs contrast with fixed costs, which remain constant throughout a financial period.

you have to put the parentheses like this:

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