What does the ac button on calculator mean?

What is importance of formula bar? Which fingers do you use for reach keys? What causes your computer to stay on after shut down is clicked? Is it true You can't delete a folder in Windows Explorer while it contains other folders and or files.? Ddr2 vs ddr3 which memory processor works better? What make a crt monitor to fade out? How do you calculate the capacity of a floppy disk? Who deliever Computers in a box that looked like a cow? What could prevent the hard drive from loading Windows 98SE when attempting to reinstall it? What is an activation key? How many people have laptops? Why did David LaMacchia's attorney think that he was not guilty of software piracy? Do a psychologist use Excel? Is hard drive data recovery possible after the hard drive has been wiped clean? What symbol will prepare a cell for entry of a formula? What are the disadvantages of a laser printer? Does a lg phone memory card work alone when downloading pics to your computer? Where to get lyric files? Does a hughes net router allow more than one PC at a time? What is synotonym for megahertz?