Try this.
Press Alt + F11 to open the VBE, click INSERT on the menu and select MODULE.
In the new Module enter the following sub, changing the worksheet index
number to the sheet you want to unhide the rows in. You can also use the
name as as string Sheets("WorksheetName")
Sub Unhide()
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets(1)
ws.Rows("34:36").EntireRow.Hidden = False
Set ws = Nothing
End Sub
Click file in the menu and select CLOSE AND RETURN TO EXCEL.
In the worksheet where the button is located, open the CONTROL TOOLBOX
toolbar and click the DESIGN MODE button. Right click the command button and
select VIEW CODE and enter the name of sub UNHIDE, without parenthesis.
Click file in the menu and select CLOSE AND RETURN TO EXCEL.
Turn DESIGN MODE off, save your workbook and give it a test drive