The world’s tallest and fastest roller coaster is at six fla

The world’s tallest and fastest roller coaster is at six flags Magic Mountain.At the start,riders are shot straight up a tower.They then begin the backward descent the cars reach a speed of 160km/h in 7s during the descent.From a point 100m from the foot of the tower,the angle of elevation of the top of the tower is 52°.Find the height of the tower,to the nearest metre.
帮我翻译一下,顺便做出来（最好能够有过程）,
2楼的，路程为什么为155.