<h2>
Answer: an underground lake</h2>
Explanation:
In general, sound (mechanical waves) travels faster in solids than in liquids, and faster in liquids than in gases. This is because <u>the speed of the mechanical waves is determined by a relationship between the elastic properties of the medium </u>in which they are propagated and the mass per unit volume of the medium (that is:<u>density</u>).
In other words: The speed of sound varies depending on the medium through which the sound waves travel.
So, if we are told the sound wave initially had a speed of 4,000 m/s and it suddenly decreases to 1,500 m/s, this means the sound waves passed from a solid medium to a liquid medium.
Hence, the correct option is: an underground lake.
I don't know what the tables you have look like but her <span>displacement</span> would be -1m
Power = (work done) / (time to do the work)
Work done = (force to lift the object) x (distance lifted)
In this question, the force is the (weight of the basket)+(your weight).
Work done = (weight of basket+you) x (3 meters)
Time to do the work = 6 seconds.
Power = (weights x 3 meters) / (6 seconds)
<em>Power = (1/2)·(weight of the basket+you, in Newtons) watts</em>
