two with south Australia and new south wales
Tennessee or Missouri; both share borders with eight states.
No states share borders with Alaska
Both Hawaii and Alaska do not share borders with any other states.
Tennessee and Missouri.
Alaska and Hawaii
Alaska and Hawaii share no borders with US States.
I guess you mean if both countries do share borders with other nations. In that case, they do: the US also borders Canada and Mexico also borders Guatemala and Belize.
Oregon, Nevada and Arizona.
Seven states share borders with Colorado.
Both Tennessee and Missouri share borders with eight other states.
Oregon, Idaho and British Columbia , Canada