B. Ensure that their results are accurate and reliable
Answer:
his speed is 5cm a second
A, the light generated from the headlights travels at a fixed speed relative to the road
Answer:
vibration
Explanation:
When the school bell vibrates, it forces the adjacent particles in air to vibrate. ... As the bell continues to move forward and backward, it produces a series of compressions and rarefactions. This makes the sound of a bell propagate through air.