In the mid-1980s, Microsoft developed the ________ operating system based on a graphical user interface with buttons, textboxes, menus and other graphical elements.

What is the major difference between a linked file and an imported file?

What will be an ideal response?

When the PC version of the spreadsheet program __________ became available, the IBM PC quickly became the top-selling personal computer.

Fill in the blank(s) with the appropriate word(s).