Rich selection of the orchestra is typically runs seating most during rehearsal and performance

If we are talking about which has the most in order it goes Violin, Viola, Cello, then the Double Bass.

Violins have the most they're a high instrument and are usually drowned out by the lower strings also carry the melody most of the time, hence, the Cello and Double Bass.

Then comes Violas, depending on the orchestra there isn't alot of people who play them for some reason but they're in between Cello and Violin.

Cello usually has a good bit but not too many to drown out the other strings.

Then the Bass the foundation of the orchestra too many can drown out, usually only have one or two

c, d, e, f, g, a, b, and c.

sometimes western music will also use solfege. the names of these are do ra me fa sol la si (or ti) and do.

to indicate a note a half step higher or lower then the original note, you would say c # (for a half a step above c) or bb (for half a step below b)