A composer, or more specifically a 'symphonist', although the latter word is not used very often.
A Librettist
A composer.
... is called the composer.
The end of a symphony is called a rondo or sonata.
Whatever the person that wrote it wants to call it. Symphonies can have all sorts of variations in number of movements. Stravinsky wrote a piece he called "Symphony in Three Movements". Mozart's "Prague" Symphony (No. 38) has only three movements and is sometimes called the symphony without a minuet. Schubert's "Unfinished" Symphony only has two movements, thought presumably it was not planned that way. In the final consideration, it's best simply to go with whatever the composer called it.
Testator.
The person who writes a check is called the payor. Or in the case of my brother, a sucker, when he writes another check for his girlfriend.
An author.
a publisist a bigraphy
a playwright
This is a poet
composer
A person who writes newspaper articles is called a journalist or a reporter.
A person who writes newspaper articles is called a journalist or a reporter.
A Librettist
hitorians
A composer.