单项选择题
A.3mm B.5mm C.10mm D.15mm
A.10℃ B.20℃ C.30℃ D.40℃
A.3~4 B.5~10 C.15~20 D.30~40
A.1/3 B.1/2 C.2/3 D.3/4
微信扫一扫,加关注免费搜题