yes
Yes, a US passport holder needs a visa to travel to Australia.
yes you can yes you can
No
Yes, you can go to school part-time as long as you maintain your L1 status. L2 dependants can study full-time.
Does not matter if you are a US Green Card holder or not, when you have an Australian visitor visa, you can go there.
A B1 visa holder can typically stay in the US for up to 6 months per visit.
A visitor visa holder can typically stay in the US for up to 6 months per visit.
The maximum duration of stay allowed for a US visitor visa holder is typically 6 months.
A B1/B2 visa holder can typically stay in the US for up to 6 months per visit.
If you are not a citizen of the US or Canada, you must have a US Visa to travel in the US.
yes
Can a US green card holder marry a filipino and petition for a spousal visa to the US