三角高程测量是根据两点的()和竖直角计算两点的高差。
A.水平距离
B.斜程
C.高差
D.高程
参考答案:A
下面漫画启示我们[ ]
①人类难以与大自然和谐共处
②乱砍滥伐会导致生态失衡、土地沙化
③人们决不能砍伐树木
④人类应尊重大自然中的各种生命,否则会自食恶果
A.②③
B.①③
C.①④
D.②④
Suspecting the traveler of carrying drugs,the Customs official stopped him and________his suitcase,
but found nothing at all.[ ]
A.looked up
B.went through
C.searched for
D.referred to