舒张压的高低主要反映以上哪项的大小()
A.每搏输出量
B.心率
C.外周阻力
D.主动脉和大动脉
E.循环血量
参考答案:C
—How are you different from before, Linda?
—Two years ago, I ______ a primary school student and now I'm taller. [ ]
A. was
B. is
C. am
D. be
用电计量装置原则上应安装在供电设施的()。
A.供电侧
B.用户侧
C.设备侧
D.产权分界处