Answer:
The frequency of a wave is measured in Hz (hertz)
From the law of atmosphere

Where
= constant and is number density where the height y = 0cm
= Number density at height y=3cm
Kb = Boltzmann constant 


Re-arranging the equation to have the value of the gravity,


Since it is 30% of value above surface, therefore 






Therefore the correct answer is C.
Answer:
infinity
Explanation:
Given that
Resistance = R
Resistivity = ρ
Length = L
Diameter = d
The resistance of wire R given as

A=Area

Now by putting the value of A


When d tends to infinity then d² will also tends to infinity.
So when d tends to zero then the resistance tends to infinity.
Therefore answer is ---
infinity
<span>Destructive Interference. This gives the effect of making the two waves disappear at the moment they meet. After the 2 waves cancel each other at the monent when they overlap, the waves continue in the same direction and magnitude as they were originally.</span>