A MB (MegaByte) equals 1048576 bytes (B) or 1024 KiloBytes (KB). or 0,00098 GigaByte (GB).
So 120 MB = 125829120 B or 122880 KB or 0.11719 GB
400 songs
Zip disks were released initially in 120Mb. this lasted for about 2 years and ultimately a 250Mb size was released. Unfortunately for the Zip drive, CD-R burners were coming in about the same time and the larger & cheaper CDs left the Zip with nowhere to go.
To calculate the page table size, divide virtual address space by page size and multiply by page table entry size. Example: for a 120MB address space with a 4KB page size, you require 30,720 page table entries. If a page table entry is 4 bytes, you require a total page table size of 122,880 or 120KB.
The super-disk or LS-120 and its derivatives are a removable disk akin to a zip disk or floppy disk. They are designed to be easily swapped from machine to machine. Physically they resemble a floppy disk in that it has an internal platter is composed of flexible plastic encased in a hard case for protection. They also had the advantage of being able to read and write standard 3.5" floppy disks, but at much higher speeds than standard floppy drives. Superdisks are generally considered to be obsolete these days, with thumb drives cd-rws and dvd-rws having taken their place as easily portable storage devices. Superdisks are/were available in 120mb 240mb, and if i recall even 480mb sizes.
Short answer: about 250,000 songs if each song is 4MB in size. Long answer: Two factors are important when figuring how many songs fit in a certain amount of space: the average size of each song, and how large a terabyte is. In my music collection, I have 21,642 music files requiring about 120MB. This works out to an average of 5.5MB per song. So the average size of each song in my collection is 5.5MB. A terabyte works out to either 1,000,000MB (according to hard drive manufacturers) or 1,048,576MB (according to everyone else). Divide the appropriate number by the average size, and you have your result. Respectively, it'll either be 180,000 songs or 190,000 songs for my own collection. Your mileage will vary.
To seed you just keep the torrent file in your application with it still on green (means that you're uploading) - this also means you can't move the file(s) to another part of your hard drive unless you relocate using the application, If you want to really reassure yourself that you're seeding, open a saved torrent file from your hard drive into your application. When the options come up, uncheck everything so you won't download. Since it won't be downloading, it will immediately go on to seeding. Average uploaders request a 1:1 upload - say you've just got a 120MB file, you're expected to upload atleast that same amount. Although the recommended would be 2:1, especially if its a relatively new torrent.