在有指向标的地图上,要根据指向标来定方向,指向标箭头一般指向( )
Most Brazilians get along well with each other, _________ they are from different races(种族), including Americans, European settlers, and Africans.
图中描述的是远视眼的成像情况,请在方框内画出可以矫正视力的透镜.
图中的均匀杆A处于静止状态,试在图上画出A所受到的弹力的方向.