单项选择题
More than（）of the population in the United States lived in city areas in 1988.
A.60% B.75% C.90% D.50%
单项选择题 One of the reasons for the growth of population in Florida is because of its（）
单项选择题 The three states that have seen the fastest growth in population in the past 20 years are（）
单项选择题 （）was an important immigration spot in late 19th century and early 20th century.
