Questions about Donuts

I just found out about Donuts & I have some questions:

1) Are Donuts similar to Moons or do we have to register for them separately?

2) Is there a minimum karma requirement or account age to be eligible for receiving Donuts?

3) Is there a penalty involved for selling Donuts? [Like future Moons distribution is affected by the % of Moons you sell]

4) What’s the Karma:Donut ratio usually like?

Thank you

submitted by /u/luci450