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• Specify a name for the spreadsheet, we chose female_only, using the Save File dialog
• Select Save to save the spreadsheet

It is best practice to occasionally save the project you are working on. Let's take the opportunity to do this now. 

• Select File from the main command toolbar
• Select Save Project...
• Specify a name for the project, we chose Methylation, using the Save File dialog
• Select Save to save the project

Saving the project saves the identity and child-parent relationships of all spreadsheets displayed in the spreadsheet tree. This allows us to open all relevant spreadsheets for our analysis by selecting the project file. 

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