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Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.

These Colloid substances consists of ultramicroscopic particles of one substance dispersed through another substance from which we cannot separate them.

Sugar water is not a colloid and it is a solution in which we can separate them.

Law of Octaves states that "If the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements." That is every 8th element have the same physical and chemical properties. This was established by the British scientist John Newlands in the year 1865.

A computer has two types of memory.

1. Non-volatile and

2. Volatile.

Volatile memory is computer memory that requires power to maintain the stored information.

* It is a temporary memeory which cannot contain information permanently.

Example :: RAM or Random Access Memory

Non-volatile memory is computer memory that can retain the stored information even when not powered.

* It is a permanent memory in which data is stored in permanently.

Examples :: Hard disc, ROM, Floppy discs, Magnetic tape,...

In the early 1950s two scientists, Rosalind Franklin and Maurice Wilkins, studied DNA using x-rays. Franklin produced an x-ray photograph that allowed two other researchers, James Watson and Francis Crick to work out the 3D structure of DNA. The structure of DNA was found to be a double helix.

The world's largest car park can hold 20,000 vehicles and is situated at the West Edmonton Mall in Edmonton, Alberta, Canada. There are overflow facilities on an adjoining car park for 10,000 more vehicles.