It requires very little space, maybe around 15 MB to start, but can get up into the gig's if you have a lot of different world saves. The single player world saves are in your ".minecraft" folder ("Application Support/ minecraft" for Mac).
Gigabytes?! It should NOT be much, unless it is a combination of 1,000s of minecraft mods. Minecraft mods take up very little space. Just be sure to have winrar or 7zip.
Depends on how much RAM you have if you have a good amount 6 gigabytes or more is pretty good for minecraft than you can search how to dedicate ram to minecraft. Or just watch this video...
You only need one, but you would need lots of DDR3 (RAM), maybe 2+ GB.
Some good mods are Toomanyitems, xray, or the moon mod if you have 1.8. They do not have much GB either. They work better in MyCraft.
Minecraft uses about 500 megabytes of RAM to play, that can vary if you change the settings.
Minecraft typically uses between 300MB and 900MB of RAM, although it can use more if you play on high settings and expand your world a lot. The game usually gets allocated 900 MB RAM by the operating system (if you have that much). Check out the official system requirements specified by Mojang in the link I have included in the Related Links section below.
There are 1024 KB in 1 GB, so you only need a fraction of a GB to hold 7.7mb
A little bit above 1 GB
Definitely
10
Between 19.45 to 25.46 mb
The Skyplayer isnt even in the GB, its in the MB.