Answer:
Visible light
Explanation:
Electromagnetic spectrum is the classification of the electromagnetic waves according to their frequency/wavelength. In order from the shortest to the longest wavelength, we have
Gamma rays
X-rays
Ultraviolet
Visible light
Infrared
Microwaves
Radio waves
All these waves are invisible to human eye, except for the part referred as 'visible light'. The electromagnetic waves of this part of the spectrum are visible to human eye, and they appear as a different color depending on their wavelength. In particular, we have:
Violet: 380-450 nm
Blue: 450-495 nm
Green: 495-570 nm
Yellow: 570-590 nm
Orange: 590-620 nm
Red: 620-750 nm
Answer:
I think it is meteorologist because they also study of the atmosphere, atmospheric phenomena, and atmospheric effects on our weather.
The needle on a compass always points in the direction of magnetic north because of the magnetic poles of earth. the compass is essentially a magnet itself, so the southern pole of the compass is attracted to the northern pole of earth.
In fact, entropy of an isolated system never decreases (2nd law of thermodynamics), unless some external energy is provided in order to "restore" order in the system and decrease its entropy.
(note that when external energy is added to the system, it is no longer "isolated").
*This is only true if the question is referring to a certain system within the universe. If we are considering the universe itself as the system, then this option is no longer correct, because no external energy can be provided to the universe, and since the universe is an isolated system, its entropy can never decrease. If we are considering the universe itself as the system, none of the options is true.