Your supervisor has requested an area on the spreadsheet that quickly summarizes sales over the past few months and shows the commission rates for those sales. In cell C$22,$ calculate the sum for the Hard Drive category $($found in A$22).$ Fill down into C$23$:C$26$ so that the calculation shows the sum for each of the categories in the A column.

Hint: You do not need a database function here, but you can't just use a simple SUM$()$ either. You need the Sum that allows you to enter a criteria that determines which numbers to sum.