Lucy ____(take) many photos in Shanghai last week.
已知函数f(x)=πcos(x4+π3),如果存在实数x1、x2,使得对任意实数x,都有f(x1)≤f(x)≤f(x2),则|x1﹣x2|的最小值是( )
Can you choose me your deskmate? I can help you with your English.
如图所示,O为直线AB上一点,OD平分∠AOC,∠DOE=90°.
“人口自然增长率等于零”的含义是表示该地区没有婴儿出生。( )(判断对错)