DNSSEC in the world ?

[Arlen Hing]

I just study how to use DNSSEC, but I find that 
if I want to use DNSSEC in my zone, it must be signed
by my parent zone. and my parent must be signed
by its parent zone and .......

so, this will get some questions. 
1. Is DNSSEC supported by root dns server ? 
2. how many dns server in the world use DNSSEC ?
3. can I use DNSSEC, without sign by my parent ?
4. is all part of DNSSEC is complete in bind9 ?