1. [单选题]医用橡皮膏的剥离强度应不低于（ ）
A. 1.1N/cm
B. 1.0N/cm
C. 0.9N/cm
D. 0.8N/cm
E. 0.7N/cm
2. [单选题]反应物消耗一半所需的时间称为半衰期 (t1/2)。公式为（ ）。
A. t1/2=0.639/k
B. t1/2=0.693/k
C. t1/2=0.369/k
D. t1/2=O.936/k
E. t1/2=0.396/k
3. [单选题]冰点降低为-0.52℃的溶液是
A.
