Both, there are two different types of molecules to distinguish that
Answer:
- 1100 J heat flows out
Explanation:
dW = - 1600 J (as work is done on the gas)
dU = 500 J
dQ = ?
According to the first law of thermodynamics
dQ = dU + dW
dQ = 500 - 1600
dQ = - 1100 J
As heat is negative so it flows out.
Answer:

Explanation:
Given that,
The ray makes an angle of 32 degrees with respect to the normal of the surface.
The refractive index of air, 
The refractive index of water, 
Snell's law is given by :



So, option (4) is correct. Hence, this is the required solution.