Misc: These letters define what - ASAP?

Questions

What fraction of a metre is a micron?

Tuscany is a major wine producing region of which country?

Which planet other than mercury does not have moons?

In order to satisfy an adults daily nutritional requirements it would be possible to drink 1 glass of orange juice, 2 glasses of milk and how many pints of Guinness?

Which actress plays Buffy the Vampire Slayer?