sinc函数和矩形函数关系？
A. 线性
B. 正比
C. 指数
D. 傅立叶变换
According to the speaker, how about the higher education tuition after World War II?
A. The tuition was very high.
B. Most students were in debt.
C. Most students depended on their parents to pay it.
D. American public colleges were free or almost free.
How about American higher education tuition 30 years ago?
A. The tuition was very high.
B. Most students were in debt
C. American higher education tuition was affordable and reasonable
D. American public colleges were free or almost free
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