— It's raining heavily outside.
— Indeed. I prefer ________ at home ________ on such a day.
A:stay; to go out
B:to stay; go out
C:staying; to going out
D:staying; going out
下列从左边到右边的变形,是因式分解的是( )
在△ABC中,a,b,c分别为内角A,B,C的对边,3cosA﹣cos(B+C)=1,a=15,B=π4,则b等于( )
读图南水北调工程示意图,完成问题. 北京所在的干湿地区( )