Ctrl-O
External means outside. An external spreadsheet is a spreadsheet that is not located in the spreadsheet file you have open at the moment.
Double click on the spreadsheet file (assuming you have the spreadsheet application loaded on your computer).
Yes it is. It is a free and open source spreadsheet program.
Yes - you can create graphs from the data in a spreadsheet.
Open it, type it, close it.
Absolutely - I use them regularly. The spreadsheet part of OpenOffice is 'Calc'
A cell is an open box on a table, and as such, yes cells are text areas on a spreadsheet.
false
false
Every spreadsheet is different. So what you do will depend on what the spreadsheet is required to do. You will type your text and numbers into cells and then add in other elements, such as formulas or charts. You can format your text and numeric data as appropriate to the spreadsheet you are creating.
An active worksheet is a spreadsheet that is visible in a workbook. When you open a new workbook, the first sheet you see is the active worksheet.
You would use a spreadsheet application such as Excel, Lotus 123, Open Office Calc, Quattro Express, Google Docs, etc. It will depend on what was used to create the original document. Some applications are capable of opening several types of spreadsheet.