Q1- If you do not specify spool and temp space, it will inherit the spool and temp space of parent that is A1 so the spool and temp space for A11 will be:
Spool = 100 GB
Temp = 100 GB
Q2- This will return an error that A1 do not have enough spool space.
Q3- This will again return an error that parent do not have enough temporary space.
You can assign 0 spool and 0 temp space while creation of a database. These spaces can be added laters.