题干
different, of, places, the, come, they, from, world(. )(连词成句)
答案(点此获取答案解析）
They come from different places of the world.
different, of, places, the, come, they, from, world(. )(连词成句)
线
，其中a为2,4,6,8中任取的一个数，b为1,3,5,7中任取的一个数，从这些抛物线中任意抽取两条，它们在与直线x=1交点处的切线相互平行的概率是
