乙炔的氧化爆炸压力为起始绝对压力的（）倍。
A.10
B.11-13
C.30
D.50
参考答案：B
皮管延迟的正确方法有（）
A.橡皮筋阻断法
B.止血钳阻断法
C.皮管血运阻断夹延迟
D.血压计延迟法
E.手术延迟
A great many teenagers became ________ playing computer games, wasting their precious time. [ ]
A. accustomed to
B. addicted to
C. used to
D. due to
