Answer:
The frequencies are 
Explanation:
From the question we are told that
The length of the ear canal is 
The speed of sound is assumed to be 
Now taking look at a typical ear canal we see that we assume it is a closed pipe
Now the fundamental harmonics for the pipe(ear canal) is mathematically represented as

substituting values


Also the the second harmonic for the pipe (ear canal) is mathematically represented as
substituting values
Given that sound would be loudest in the pipe at the frequency, it implies that the child will have an increased audible sensitivity at this frequencies
Answer:
Frequency, f = 1 unit
Explanation:
It is given that,
Period of the wave, T = 1 unit
We need to find the frequency of the wave. There exist an inverse relationship between period and the frequency of the wave. It is given by :

Or


f = 1 unit
So, the frequency of the wave is 1 unit. Hence, this is the required solution.
Answer:
C. microscope
Explanation:
A simple microscope is magnifying glass, an ordinary double convex lens having a short focal length that produces virtual and erect image.
Answer:
temperature
Explanation:
when you put a water on the stove the water will start to boil there for temperature