带传动中,带轮的包角不应小于()。
A、120°
B、90°
C、180°
D、360°
参考答案:A
关于烟曲霉菌镜下形态,叙述错误的有()
A.顶囊呈烧瓶状
B.产孢细胞单层或双层分布在顶囊上半部分
C.菌丝分隔透明
D.孢子梗壁粗糙不平
E.分生孢子球形、绿色,有小刺
If farmers trees and forests, giant pandas nowhere to live. [ ]
A. cut down; have
B. will cut down; will have
C. will cut don; have
D. cut down; will have