Misc: Who sang arthur's theme (best that you can do)?

Questions

Britain opened its offensive on the Western front during WW I.?

US's first commercial radio, 8MK (later WWJ), Detroit began daily broadcasting?

Jacqueline Susann, writer (Valley of the Dolls), born.?

Jean-Loup Chritien, first French traveler in space (on Soyuz T-6), born.?

Dumont's first TV Broadcast for home reception, NY city.?