Drag is the force pushing against a forward motion.
Answer:
photons
Explanation:
The energy of a photon is given by

where
is the Planck constant
is the speed of light
is the photon wavelength
Here we have

So, the energy of 1 of these infrared photons is

The amount of energy needed to increase the temperature of the cup of water is:

where
m = 175 g is the mass
is the specific heat capacity
is the increase in temperature
So,

Therefore, the number of photons needed is:

D.The transferring of thermal energy from the sun to the earth!
Answer:
the scientific study of the relations between heat and other forms of energy