Answer:

Explanation:
P = Acoustic power = 63 µW
r = Distance to the sound source = 210 m
Acoustic power

Threshold intensity = 
Ratio

Ratio of the acoustic intensity produced by the juvenile howler to the reference intensity is 113.68
Answer:
420m
Explanation:
Given parameters:
Time = 5minutes
Average speed = 1.4m/s
Unknown:
Distance covered = ?
Solution:
Speed is the rate of change of distance with time.
Mathematically;
Speed =
Distance = speed x time
Insert the parameters and solve;
Convert the time to seconds;
1 minute = 60s
5 minute = 5 x 60 = 300s
So,
Insert the parameters and find the distance;
Distance = 300 x 1.4 = 420m
Answer:
-6.49 m/s
Explanation:
This is doppler effect.
The equation is;
F_l = [(v + v_l)/(v + v_s)]F_s
Where;
F_l is frequency observed by the listener
v is speed of sound
v_l is speed of listener
v_s is speed of source of the sound
F_s is frequency of the source of the sound
In this question, the source of the sound is the moving vehicle.
Thus;
F_l = F_beat + F_s
We are given beat frequency (f_beat) as 5 Hz while source frequency (F_s) as 260 Hz.
So,
F_l = 5 + 260
F_l = 265 Hz
Since listener is sitting by car, thus; v_l = 0 m/s
Thus,from our doppler effect equation, let's make v_s the subject;
v_s = F_s[(v + v_l)/F_l] - v
Speed of sound has a value of v = 344 m/s
Thus;
v_s = 260[(344 + 0)/265] - 344
v_s = -6.49 m/s
This value is negative because the source is moving towards the listener
2.5 that would be the corect answer hope this helps
The graph is one single line and, as a system solution refers to an intersection point (in other words, a point in common), we affirm both equations share all of their points and thus, such system has infinite solutions.