In each of the following cases, determine whether the United States has jurisdiction to tax Mrs. CM.
a. Mrs. CM is a citizen of Brazil but is a permanent resident of Orlando, Florida.
b. Mrs. CM is a citizen and resident of Brazil. She owns Manhattan real estate that generates $100,000 net rental income annually.
c. Mrs. CM is a citizen and resident of Brazil. She owns no property and conducts no business in the United States.
d. Mrs. CM is a U.S. citizen but is a permanent resident of São Paulo, Brazil.