This is a website that converts it for you: http://egret.net/kb__mb.htm
1 Gigabyte (1GB)
1024
There are 1024 megabites in 1 gigabite. 20 gigabites has 20,480 megabites.
It depends on how many gigabites it has like 8 gigabites can hold about 15 movies.
None
4500
5500
4,000,000,000
a half
100
1.306728 gb
A lot.