酸中毒时，血钾浓度的变化趋向是
A．升高B．下降C．无变化D．先低后高E．先高后低
参考答案：A
-He says that my new car is a ________ of money.
-Don't you think those words are just sour grapes?[ ]
A. lack
B. load
C. question
D. waste
在只考虑地势的情况下，三条河流水流速度最慢的是（ ）
A．ab段
B．ed段
C．ef段
D．一样快
