单项选择题
A. it increases the danger of war B. it provides services to both the good and the malicious C. it makes distant communication easier D. it breaks up the multi-generational household
A. 9 million B. 6 million C. 90 million D. 20 million
A. $100 to $200 B. $200 to $400 C. $400 to $500 D. $500 to $600