Answer:
A. Air
Explanation:
A thermal insulator is a material that does not let the heat trasmitting through it, or it transmits heat not very efficiently.
Generally, the lower the density of the material, the better insulator the material is: this is because in materials with very low density, particles are very spread apart, so they cannot collide with each other, and so the vibrations of the particles (which determine how hot a substance is) cannot be transmitted very efficiently.
In the options listed in this problem, air is the material with lowest density, therefore it is the best thermal insulator among them.
It'll have a higher frequency.
The product of (wavelength) times (frequency) for a wave
is always the same number ... it's the wave speed.
So if one of them is small, the other one has to be big.
The resultant force on the animal = Resultant mass * total acceleration
F = 0.2 * 2.5 to the right
F = 0.5 to the right.
As, girl exerting a force of 3.5 N & it's not mentioned that she is in right or left, so the force exerting by boy would be either:
3.5-0.5 = 3 OR 3.5+0.5 = 4
If boy exerting a greater force then, answer will be 4 N & if girl exerting a greater force the, answer will be 3 N
Hope this helps!
734 is the answer for the chronic blood exchange service of new france