已知：如图，在平面直角坐标系xOy中，正比例函数$y=\frac{4}{3}x$的图象经过点A，点A的纵坐标为4，反比例函数$y=\frac{m}{x}$的图象也经过点A，第一象限内的点B在这个反比例函数的图象上，过点B作BC∥x轴，交y轴于点C，且AC=AB．求：

中山大信商场一楼到二楼的自动扶梯高度是4m，扶梯长6m。小明同学体重500N，自动扶梯把小明同学从一楼运送到二楼的过程中对他做功____ J。如果要测算自动扶梯对他做功的功率，还应该测量的物理量是____ 。

阅读柳宗元的《溪居》一诗，完成题目。
                                                                                                                                    溪 居^①
                                                                                                                                      柳宗元
                                                                                           久为簪组^②束，幸此南夷谪^③。闲依农圃邻，偶似山林客。
                                                                                          晓耕翻露草，夜榜^④响溪石。来往不逢人，长歌楚天^⑤碧。
【注】①这首诗是柳宗元贬官永州居处冉溪之畔时的作品。②簪组：古代官吏的服饰，这里是做官的意思。 ③南夷：这里指当时南方的少数民族地区。 谪：被降职或调往边远地区。④夜榜：夜里行船。榜：此处读“彭”音，意为进船。此句指天黑船归，船触溪石而发出的声音。⑤楚天：永州古属楚地。

   Science has told us so much about the moon that it is quite easy to form an idea of what it would be like to go there. It is certainly not a friendly place. As there is no air or water, there can be no life of any kind. Mile after mile there are only plains(平原) of dust with mountains around them. Above, the sun and stars shine in the black sky. If you step out of the mountains shadows, it will mean moving from terrible cold into great heat. The moon is also a very silent(安静的) world, for sound waves (声波)can only travel through air. But from the moon, you can see a friendly sight(景色). Our earth is shining more brightly than the stars. It looks like a large ball, coloured blue and green and brown.