i think the answer is B police siren.
The answer to the question is:
75m/s
Just do 25*3
Two. The both have a plasma membrane and cytoplasm.
Answer:

Explanation:
If we have a periodic wave we need to satisfy the following basic relationship:

From the last formula we see that the velocity is proportional fo the frequency.
For this case we have the following info given by the problem:

We know that the frequency is the reciprocal of the period so we have this formula:

And if we replace we got:

Now since we have the value for the wavelength we can find the velocity like this:

And if we convert this into cm/s we got:

Answer:
f=1.92 cm
If ans is correct reply for explanation.