矢状位胸腺垂直径最大约为()
A.1~2cm
B.3~4cm
C.5~7cm
D.8~9cm
E.以上均不是
参考答案:C
解析:矢状位胸腺垂直径最大约为5mm~7mm。
I didn’t understand ________________ , so I raised my hand to ask him.
A.what my teacher says
B.what does my teacher say
C.what my teacher said
D.what did my teacher say
二苯碳酰二肼分光光度法测定水中六价铬时,显色酸度一般控制在0.05-0.3mol/L(1/2H2SO4)以()mol/L时显色最好。显色前,水样应调至中性。显色时,()和()对显色有影响。