Create a new worksheet named Summary that has the same layout as the monthly worksheets

Position it to the left of the January worksheet.

In each of the numeric cells of the Summary worksheet enter a formula that uses cross sheet references to sum up the values from the monthly worksheets.

You must write a formula in the upper left cell (C7) that you can copy down and across to all the cells of the table.

Your formula should use the SUM function.

DO NOT write a function that looks like this: SUM(MonthX!C7,MonthY!C7,... or like this SUM(MonthX!C7+MonthY!C7,...

What does this mean and how do you write the SUM function different?