Marrakesh express was written by Graham Nash and recorded by Crosby, Stills & Nash

If you're referring to 'The Sound of Silence', that was written and performed by Simon and Garfunkel, not The Beatles.

Simon and Garfunkel certainly have their own unique sound. Many folk bands of the same era, like Crosby, Stills, and Nash, or solo artists like Cat Stevens, have a similar sound.

Arthur

He was known as Art.

Joeseph Conlan was supposedly the composer although Barry De Vorzon did a few episodes - Ill be Joeseph would know

the song "Claire" is by Gilbert o'Sullivan (of "alone again, naturally" fame). the song is about his niece.

i heard that they postponed the show because Art had some kind of throat problem. i sincerely hope they reschedule.

They didn't

Paul Simon is the lead voalist on "America" from the "Bookends" album. Art Garfunkel adds harmonies throughout the song>

That line's from "Mrs. Robinson" (featured in the movie The Graduate).

Paul Simon did

Simon and Garfunkel, known as Tom and Jerry in the late 50's, changed their name to Simon and Garfunkel in the early-60s producing their first album ("Wednesday Morning, 3 A.M.") together in 1964.

yes

The Graduate

IDK I don't know what they called each other. why do u care?

No. "Mrs. Robinson" came out a few months prior to "I Am the Walrus". Also, in "Mrs. Robinson", they say "koo-koo k'choo", not "goo-goo g'joob".

Yes. Paul Simon had first heard the song performed by a French folk group, who told him it was a very old traditional song, when in fact it had been written and registered in 1933. Later, the composer's son sued for copyright infringement in what is generally referred to as a "very friendly" case. An article about it (in Spanish) is available at the link below.

"59th Street Bridge Song"