DSA显示血管的能力与血管内碘浓度和曝光量平方根的乘积成 A．正比 B．反比 C．

A first-grade teacher use ten flash cards, numbered 1 through 10, to teach her students to order numbers correctly. She has students choose four flash cards randomly, then arrange the cards in ascending order. One day, she removes the cards numbered "2" and "4" from the deck of flash cards. On that day, how many different correct arrangements of four randomly selected cards are possible ？（）

A.70

B.210

C.336

D.840

E.1，680

感染后约8％～33％演变为慢性肝炎的是

A．气滞血瘀
B．肝胆气郁
C．肝胆湿热
D．阴虚郁滞
E．结石梗阻

学术论文或总结必须写摘要，且字数不得超过300字。( )

旅游饭店星级的划分与评定释义中规定，三星级饭店的中餐厅要求（）。

A.规模适当

B.装饰豪华

C.氛围浓郁

D.高档消费

T形槽铣刀强度较低，排屑又困难，故应选用较高的铣削用量。