Answer:
It would be hard to test scientifically since it's subjective and can only be proven true if you conducted some experimentations and observations.
Answer:
The values is 
Explanation:
From the question we are told that
The speed of the fire engine is 
The frequency of the tone is 
The speed of sound in air is 
The beat frequency is mathematically represented as

Where
is the frequency of sound heard by the people in the fire engine and is is mathematically evaluated as
![f_a = [\frac{v_s + v }{v_s -v} ]* f](https://tex.z-dn.net/?f=f_a%20%20%3D%20%20%5B%5Cfrac%7Bv_s%20%2B%20v%20%7D%7Bv_s%20%20-v%7D%20%5D%2A%20f)
substituting values
![f_a = [\frac{340 + 5 }{340 -5} ]* 500](https://tex.z-dn.net/?f=f_a%20%20%3D%20%20%5B%5Cfrac%7B340%20%2B%205%20%7D%7B340%20%20-5%7D%20%5D%2A%20500)

Thus


A solid has a definite meaning that there is only one shape there can be meaning a solid has a definite volume
Answer:
<em>F equals 3 N and the object remains stationary</em>. (second option in the list)
Explanation:
For sure to cancel acting forces, F must be 3N pointing up. But with regards to the object stationary or not, the question is tricky. We could have a ZERO net force applied, and the object moving at constant speed, which could still verify Newton's Laws. But considering the first answer option that refers to vertical motion upward where the object could be gaining potential energy, the most accurate response is that the force F has to be 3 N pointing up to make the object in equilibrium, and no motion in the vertical axis.
The formula for accelerational displacement is at^2/2, so we know that 3.9t^2/2 = 200, or 3.9t^2 = 400. t =

, at = v, so