Answer:
I believe it's 2) sound waves
Explanation:
With sound waves, the energy travels along in the same direction as the particles vibrate. This type of wave is known as a longitudinal wave, so named because the energy travels along the direction of vibration of the particles.
(First, I guess you chose the wrong subject since this is English not Physics :p)
Now, the pronouns are words that take the place of a noun.
The Personal pronouns are: I, you, he, she, it, we, they.
I, you, he, she, it are singular; while we and they are plural.
So, in the sentence, we can clearly see the pronoun "we", which is a plural pronoun.
So the plural pronoun in this sentence is We (Answer D)
Hope this Helps! :)
The acceleration of the car which changes the speed uniformly is 4 m/s²
<h3>What is acceleration?</h3>
Acceleration can be defined as the rate change of velocity with time.
acceleration a = (Δv) / (Δt)
Given is the initial velocity 6m/s and final velocity 42m/s, the time take fir this change in speed is 9s.
Substitute the values, we have
a = (42-6)/9
a = 36/9
a =4 m/s²
Thus, the acceleration is 4 m/s²
Learn more about acceleration.
brainly.com/question/12550364
#SPJ1