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.
The shell itself is made of bone, and the outer covering of the shell is made of keratin, much like human fingernails. Each shell is made up of sections called scutes. As the turtle grows, new layers of keratin are formed around the outer edges of each scute, looking much like the growth rings of a tree.