() was the last continental state added to the Union.

单项选择题The state of() is bought from France for $15 million.

A. Virginia
B. Oregon
C. Louisiana
D. Arizona

单项选择题Washington D.C. is named after ().

A. George Washington, the 1st American president
B. Christopher Columbia, the discoverer of the American continent
C. Both George Washington and Christopher Columbia
D. Neither of them