IP1 Class Test (May 2025) Q16

A hiker (Hiker I) starts climbing the mountain at minute-zero. Meanwhile the other hiker (Hiker II) is at the mountain top, starting to go down. There is a supply station in the middle of the mountain, where both hikers stop by to take a rest. The height-time graph below shows the height the two hikers are at with respect to time.

1. From the graph, find the height of the supply station.[1]
2. From the graph, find the duration of time in minutes
   1. for Hiker II to descend to \(400\) m in height,[1]
   2. Hiker I spends at the supply station.[1]
3. Find the gradient of each of the following line segments, and state clearly what each gradient represents.
   1. \(FG\),
   2. \(DK\).[4]
4. From the graph, will the two hikers meet each other on their journey? If yes, state the time when they meet each other. If no, state your reason. Assume that there is only one road on the mountain.[2]
5. Find the duration of time when the difference of height between the two hikers is less than or equal to \(200\) m.[1]