A:春季
B:夏季
C:秋季
D:冬季
在-3,π2-1,-2x-2,-1πx2y,-a-12,-x4六个代数式中,是单项式的个数( )
设O为坐标原点,A(1,1),若点B(x,y)满足x2+y2≥10≤x≤10≤y≤1,则OA→·OB→取得最小值时,点B的个数是( )
如图所示为玉米激起传粉方式示意图,由此可以判断,玉米花是( )
A:____that?
B: It's a radio.
A:____often listen to the radio?
B:____, I do.
A:____do you often listen to?
B: I often listen to music.
A:____do you often listen to the music?
B: In the park or at home.
①刘某在私营企业工作,他获得的工资收入
②王某为农村集体经济组织的成员,他获得的土地承包收入
③低收入居民李某从所居住社区获得的社会福利性收入
④孙某在国有企业工作,他获得的工资、奖金