C. BAT <span>can detect sound at a frequency of 67,000 Hz.
</span>
An elephant's frequency range is 16-12,000 Hz.
A tree frog's frequency range is 50 - 4,000 Hz
<span>A dog's frequency range is 67 - 45,000.</span>
The first and third choices could both do it, but the first choice makes a much better, clear demonstration.
Answer : The correct option is, (D) 278 K
Explanation :
We are given temperature
.
Now the conversion factor used for the temperature is,

where, K is kelvin and
is Celsius.
Now put the value of temperature, we get

Therefore, the temperature 278 K is equal to the 
Answer:
longitudinal waves have those properties
Answer:
0.4
Explanation:
F-Fr=ma where F is applied force, Fr is friction, m is mass and a is acceleration.
Since the mass is moving with a constant velocity, there's no acceleration hence
where N is the weight of object and \mu is coefficient of kinetic friction.
the subject

Substituting F for 8 N and N for 20 N

Therefore, coefficient of kinetic friction is 0.4