Misc: what was the name of the central character in the tv series "roots"?

Questions

What English china company has a lion as it's logo?

What english city was known to the romans as venta bulgarum?

What english writer said 'give me a decent bottle of poison and i'll construct the perfect crime'|agatha christie?

What entertainer's nickname is "the thief of bad gags"?

What era were the first traces of land life believed to appeared?