呈类球形、椭圆形或不规则团块，表面棕褐色至黑褐色，体重，质坚实的药材是（）
A.灵芝
B.猪苓
C.海藻
D.茯苓
E.冬虫夏草
参考答案：D
The most important thing ____ when ____an emergency is to stay calm.
A．keep it in mind; deal with
B．keep in mind; dealing with
C．to keep it in mind; dealing with;
D．to keep in mind; dealing with
某轮计划由23°10′.2N，106°26′.5W，航行到52°55′.0N，173°00′.0E，则该轮的大圆始航向为（）。
A．319°
B．041°
C．049°
D．311°
