A:How was your last summer holiday?
B:How did you go there?
某人不小心手臂擦破皮,渗出一点血迹,这时可以采取的措施是( )
已知sinA=0.1782,则锐角A的度数大约为( )
如图所示为四冲程汽油机工作过程中某一冲程的示意图,它表示的是( )