Even casual Excel users have probably encountered a situation where they wanted to test a formula against a range of possible input values. One way to do this is by simply copying a formula down a column or row of your table. A more structured way of doing this, though, is Excel's Data Tables (What-if Analysis) feature. Most K201 students don't usually have much trouble with figuring out how this feature works, but it can be easy to forget under the pressure of an exam.
Actually, the trickiest thing we cover in this video is defining custom data formats. We're not sure why, but K201 GPs and exams usually like to ask you to create custom data formats as a followup to two-variable data table questions.