Misc: What everyday element is 755 times heavier than air?

Questions

Trivia : How many years old was the telephone before one was installed on the desk of the President of the United States?

Trivia : Which singer went solo after performing with the Commodores?

Trivia : Who said , "Marriage is a wonderful invention - but so is the bicycle repair kit"?

Trivia : In which athletics event would you perform a "Fosbury flop"?

Trivia : Only one modern olympic games was not named after the host city - The "Interim Olympic games" of 1906, but what city hosted it?