Answer:
Explanation:
s = s₀ + v₀t + ½at²
s = 0 + 0(15) + ½(6)(15²)
s = 675 m
Not sure what the free fall acceleration is needed for, but if the object is dropped from a high enough point, it will travel in 15 seconds
s = ½10(15²) = 2250 m if air resistance is ignored
We use the formula,
m = V\rho
Here, m is the mass, V is the volume and
density
Also

Here l is length, w is width and h is height.
(a) The volume of the room,

The volume of the room in cubic feet,

(b) Now the mass of the air in room,
.
Therefore, the weight of the air in room,
.
The weight of air in the room in pounds,

There's a crest and a trough in each complete wave. So the question is describing 10 complete waves.
After that, the question becomes somewhat murky. It goes on to say "its time period is 0.2 seconds".
-- The "time period" of a wave is usually defined as the time for <u><em>one</em></u> complete wave. If that's what the phrase means, then ...
Frequency = ( 1/0.2sec )
<em>Frequency = 5 Hz.</em>
<em>= = = = = = = = = =</em>
<u>BUT</u> ... Is the question awkwardly trying to tell us that the <u><em>10 waves</em></u> take 0.2 seconds ? If that's what it's saying, then ...
Frequency = (10) / (0.2 sec)
<em>Frequency = 50 Hz .</em>