What's your name?[ ]
A. Hi! Nice to meet you!
B. Hello! Teacher.
C. My name is Li Ming.
答案:C
正方形周长和边长成______比例关系,正方形面积和边长成______比例.
()是指不穿透皮肤或进入身体无菌环境,但密切接触粘膜或受损皮肤的设备。
A.无风险设备
B.低风险设备
C.中级风险设备
D.高风险设备
E.极高风险设备