Translation:Marcus lives in America.
Does it mean America as in the continent or does it refer USA?
In Duolingo refers to USA. I suppose the neologism in Latin refers to the New World, like in Persea americana (scientific name of avocado) or this example https://la.wikipedia.org/wiki/America
Knowing Duolingo probably refers to the USA
Why would this be "in America" rather than "in Americam"?
In Americam would mean into America