光纤的芯径直径仅为(),仅为铜芯直径的五分之一左右。
A.0.08mm
B.0.1mm
C.0.16mm
D.0.2mm
参考答案:B
________do you want?[ ]
A. How much broccoli
B. How much broccolis
C. How many broccoli
D. How many broccolis
不需要强制检定的仪器有()
A.冰箱
B.血球计数器
C.电离辐射防护仪
D.体重秤