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<u>Air pressure has no effect at all in an ideal gas approximation. This is because pressure and density both contribute to sound velocity equally, and in an ideal gas the two effects cancel out, leaving only the effect of temperature. Sound usually travels more slowly with greater altitude, due to reduced temperature.</u>
Answer:
t = 3 seconds
Explanation:
Given that,
Initial speed, u = 30 m/s
Final speed, v = 0
It slides 45 m to rest.it take the box to come to rest
We need to find how long it take the box to come to rest.
Let a be the acceleration and t is time.

Now finding time.

So, the required time is 3 seconds.
The answer is Decibels. <span />
Answer:
Decreases/Reduces
Explanation:
Fill in the blank:
Consider the equation Work = Force X Distance.
<em>If a machine increases the distance over which a force is exerted, the force
</em>
<em>required to do a given amount of work</em> .........
If the work is a constant value, then by isolating force from the equation, we get:
Force = Work / Distance
By increasing the value of the Distance, then the quotient Work. Distance diminishes, and therefore the required force decreases (diminishes, reduces)
Answer: Decreases/Reduces
Human lack chlorophyll, which is the function that collects energy from the Sun to conduct photosynthesis.