Abstract qs

[Chris Warwick]

There seems to be very little info on abstract methds / classes in the docs, 
basicly it lists it as a storage class and thats all. So..

Does a class with abstract methods need to be declared abstract aswell?

Do all the abstract methods need to be implemented before it the derived 
class can be instantiated?

can i do ablock of declarations like this...

public abstract:
void foo();
int bar();
void fooBar(int i);

cheers

cw