物体通过凸透镜可成( )
A.正立、缩小虚像
B.正立、放大虚像
C.倒立、放大虚像
D.正立、放大实像
凸透镜成倒立像时,都是实像,成正立像时,是放大的虚像.
故选B.
根据句意,用括号内所给单词的适当形式填空。
1. My grandfather wants to live in a place which is _____ (peace) than here.
2. Male _____ (wolf) will protect their families if there is danger.
3. The dolphins were really tired because of the long _____(perform).
4. If farmers keep _____(take) the land, giant pandas will have nowhere to live.
5. Hunters will make a lot of money if they sell _____(elephant) tusks.
用代数法化简逻辑函数常用的方法有()。
A.并项法
B.吸收法
C.消项法
D.移项法
E.配项法