On May 22, a Han taxi driver an old lady to the hospital as soon as he could in Xinjiang.
A:sent
B:sends
C:is sending
D:has sent
如图所示,用瓶起开启瓶盖.请标出支点,并画出动力臂L1及阻力F2的示意图.
已知函数y=ax(a>0且a≠1)在1,2上的最大值与最小值之和为20,记f(x)=axax+2.
(1)求a的值;
(2)求f(x)+f(1﹣x)的值;
(3)求f(1n)+f(2n)+…+f(n-1n)的值.
Mr White thinks that this picture is an art____(珍宝).
下列选项中体现关爱生命健康的是( )