现有pH=a和pH=b的两种NaOH溶液,已知b=a+2,将两种溶液等体积混和后,所得溶液的pH接近于( )
A.a-lg2
B.b-lg2
C.a+lg2
D.b+lg2
答案:B
— Susan,. why are you still here? They are all ready to start.
— I'm sorry, but I ______ when to meet. [ ]
A. don't tell
B. haven't told
C. wasn't told
不是铅尘进入婴儿体内的主要途径是()
A、口动作
B、皮肤
C、玩耍过程中不知不觉摄入体内
D、呼吸系统