1 These can be two Excel files or an Excel File and a Microsoft Word file for example. 2  Press and hold down the Alt key on the keyboard. 3  Press and release the Tab key on the keyboard without letting go of the Alt key. 4  The ALT-TAB Fast Switching window should appear in the middle of your computer screen. Open at least two files in Windows. 2  These can be two Excel files or an Excel File and a Microsoft Word file for example. 3  Press and hold down the Alt key on the keyboard.
Merge this question into. Split and merge into it. Answer by Quirkyquantummechanic. Confidence votes 77.6K. Almost all of a mollusk shell is composed of calcium carbonate. It may take a few different forms and thereby appear differently, but CaCO3 is the main material in the shell.
Mollusk Shells. Many species of mollusks such as scallops, snails, mussels and oysters possess an obvious external shell that helps protect the animal from predators. The shell also helps protect species that inhabit tidal zones from the threat of desiccation by trapping life-sustaining moisture and oxygen.ther species such as scallops and oysters have two shells hinged together. These species are often called bivalves in reference to the pair of shells which are also referred to as valves. The third group, the chitons, has eight overlapping plates arranged in a row.