Yes
A Canadian citizen with a green card can use their Canadian passport to exit the US and use their US green card to re-enter the US under the same status. Hope this helps.
Yes, a green card holder can marry a non-citizen.
Yes, you can travel to Jamaica with a green card.
Yes, you can travel to London with a green card.
Yes, you can travel to Paris with a green card.
No. NTSA guidelines require a passport (foreign or US), US passport card, green card or US drivers license or non-drivers license.
Yes, individuals with a green card can travel to Mexico.
No. He also needs a visa issued by the Canadian government.
Apply at the appropriate consulate or embassy
Yes, a person with a green card can travel to Jamaica.
No, you do not need a Green Card to go to Hawaii unless you are NOT a US Citizen. It is in the Union, not outside the country. It is the same as traveling from Wyoming to Colorado. If you are not a US Citizen you will need a Green Card- the same rules that apply to the mainland apply to Hawaii.
No. A green card is issued to foreign nationals residing in the US.