Spreadsheets/Spreadsheet quiz questions

These questions can be used for a classroom trivia-quiz-style game where people are in teams of 3 or 4, or just to recap your own knowledge!

Beginner

Identify three current Spreadsheet applications that are available (But not different versions of the same product! Bonus points for each extra one)
Identify the file extension of spreadsheet documents on your computer
What must every formula in a spreadsheet start with? an equal to sign

Explain what the "autofill" feature of spreadsheets does.
The cell A3 contains the value 5. You want to add a formula into another cell that multiplies the value in A3 by 100. Write the formula required.
The cells in column A contain prices (such as 5.95, 7.95). Add a formula to the cell B3 that will calculate the GST (10 percent of the corresponding value in column A). Bonus 2 points: Add a formula in C3 to calculate the total price including the GST.
Draw and name 3 pictures of three different types of charts that you can create in your spreadsheet program (Bonus 1 point for every extra one)
Describe how you would add a footer to your printed spreadsheet.

Identify three different file-formats that you can use when you save your spreadsheet files (1 bonus point for each extra one, 3 bonus points if you can identify an ISO standard file format)
Calculating age question (Column A has peoples birth year, how would you calculate age)
The cells in column A contain prices (such as 5.95, 7.95). A special cell, cell G1 has the current GST rate of 10%, but word on the street is that it may change. Add a formula to the cell C3 that will calculate the GST so that this formula can be "autofilled" down.
The cells in column A contain prices (such as 5.95, 7.95), but some of the items are GST-free items. This is indicated by a value in column B (GST-Free column) of either "Yes" or "No". Add a formula to cell C3 that will calculate the final price for the items.