The answer is purly subjective and, thus, cannot be found here.
The trombone player.
Trombone are different for everyone so I recommend you go to a band shop and just try out their trombone and see what brand you like best.
A small Trombone.
A trumpet player will probably be able to make a sound on the trombone, but a lack of skill in using the relatively large mouthpiece on a trombone will result in a low quality sound at best. Plus, playing a valved trumpet will usually not make for an easy experience trying to learn a slide trombone.For a bit of fun, ask a trombone player in your band if you can try his instrument out. Try using your trumpet mouthpiece to see what it's like.
12c is standard for new trombone players
Yes he played the piano and the trombone. He was for a time a professional trombone player.
at the back. I think
The player's lips vibrate.
William F. Raymond has written: 'The trombone and its player' -- subject(s): Trombone
By moving the "slide"
When playing a Trombone the player can make it slur. By blowing and moving the valves at the same time.
That would be the trombone. The trombone has a main slide instead of valves to alter the length of tubing that the vibrating air has to travel through to change the pitch of notes. All brass instruments have tuning slides to slightly lengthen or shorten the tubing length to help tune the instrument.