Answer:
The material effects the speed if sound.
Explanation:
A denser material whose atoms are tightly packed will quickly transfer energy as they are close to each other than mediums like air.
Answer:
The density is 
Explanation:
From the question we are told that
The weight in air is 
The weight in water is 
The weight in a unknown liquid is 
Now according to Archimedes principle the weight of the object in water is mathematically represented as

Where
is he mass of the water displaced
substituting value


Now according to Archimedes principle the weight of the object in unknown is mathematically represented as

Where
is he mass of the unknown liquid displaced
substituting value


dividing equation 2 by equation 1


=> 
Now since the volume of water and liquid displaced are the same then

This because

So if volume is constant
mass = constant * density
Where
is the density of the liquid
and
is the density of water which is a constant with a value 
So


Answer:
Magnetic field can be used to produce current, infact a changing magnetic field can produce current.
A changing magnetic field in a loop causes the flux linked with the loop to change in turn generating a emf in the loop and therefore a current.
For a loop of area A and resistance R.
I =dPhi/dt/R
В. А
I = AcosФ/R .dB /dt
But it isn't reasonable to say that we can create a magnetic field by having a flow of current and this can be used to make more current because the current generated due to change in magnetic field created by increase/decrease in flow of current will be in a direction such that it will counter act the change in magnetic field caused by increase/decrease in current flow.(lenz's law).
We were unable to transcribe this image
Ф= В. А
I = Acos dB Rd
so as this ant moves
5 cm every second you multiply 5 by 120 (60 per minute as there are 60 seconds in a minute)
this is 600 cm
or
6 meters