成型震源药柱的密度一般为()。
A.0.50-0.65克/立方厘米
B.0.68-0.75克/立方厘米
C.1.2-1.4克/立方厘米
D.1.5-1.68克/立方厘米
参考答案:C
The government is asked to improve school bus safety, ______? [ ]
A. didn't it
B. hasn't it
C. isn't it
D. doesn't it
被狂犬咬伤的伤口最好采用()
A.弱酸冲洗
B.20%肥皂水冲洗
C.H2O2冲洗
D.食醋冲洗
E.90%乙醇冲洗