Hi, you've asked an incomplete question. The missing part of the question is shown in the attached document.
Explanation:
After performing the stated activity we could observe the following:
1. The ruler went in the opposite direction after it was released.
2. The ruler had a plain movement.
3. Depending on the length of the ruler, we could notice the "pitch" was high with a shorter ruler and low with a long ruler.
4. Yes, the sound later tops suddenly. The reason for this was that the air supply around the ruler was reduce when it was held making the vibrations to stop.
