(1) This film outlines the lives of three men who played majors roles in the dev

(1) This film outlines the lives of three men who played majors roles in the development of radio. Write down some brief notes (biographical, inventions, etc.) for the following: 50 words each
Lee de Forest
Edwin Howard Armstrong
David Sarnoff
(2) Italian inventor Guilielmo Marconi played a major role in inventing wireless (radio) telegraphy—the ability to send the dots and dashes of telegraphy through radio frequencies. What did he not conceive of?
(3) What was the significance of the Audion tube?
(4) What was the “surprise” that ship operators heard coming their wireless telegraph headsets on Christmas eve, 1906?
(5) Which inventor, described by other radio engineers as a “true genius”, would “spend a lifetime defending his work against the false claims of others”?