—What is the of the sign on the bottle?—It “Keep away from the children”.
如图,将一根长24cm的筷子,置于底面直径为5cm,高为12cm的圆柱形茶杯中,设筷子露在杯子外面的长为acm(茶杯装满水),则a的取值范围是____
下列物质的化学式,书写正确的是( )
***成立以后,最早来黄石传播革命真理和开展建党工作的是( )