Misc: Who is Dick Tracy's sweetheart?

Questions

Which much loved character was killed off in a fire on BBC radio to compete for an audience tuning in to the first ITV broadcast?

How many toes does a cat have on its front paw?

What is the style of decoration that gives the illusion of three dimensional reality to painted surfaces?

What is the more respectful name for a "trickcyclist"?

What is the hybrid of the grapefruit and the tangerine?