A:0 N
B:20N
C:10N
D:小于5N
已知点P(x,y)在经过A3,0,B1,1两点的直线上,则2x+4y的最小值为( )
—It is raining hard, _______the farmers are still working in the field. —So they are.
如图所示.将底面积为100cm2,重为5N的容器放在水平桌面上,容器内装有重45N,深40cm的水. 求: