有一个周长是785米的圆形花园，周围以等距离种白杨树157棵，两棵树间的距离是 ( )
A．4
B．5
C．6
D．7
参考答案：B
非处方药分为甲、乙两类是根据药品的：
A．安全性
B．质量标准
C．适应证
D．价格
E．品种和规格
The senator agreed that his support of the measure would jeopardize his chances for reelection.
A. benefit B. endanger C. hinder D. disturb
