Answer: The green house effect is best described by option 4 (Energy given off by earth is reflected off of earth's atmosphere back down to the surface).
Explanation:
The green house effect can be described as the energy given off by earth is reflected off of earth's atmosphere back down to the surface.
When energy from the sun passes through the atmosphere, some are absorbed which keeps the earth surface warm. While the rest is reflected back largely by cloud.
The energy which is emitted from the earth surface is called the infrared radiation. Some of the infrared radiation passess through the atmosphere but most is absorbed and re- emitted in all directions by the greenhouse gas molecules and clouds. This effect warms the earth surface and the lower atmosphere. Therefore this statement (Energy given off by earth is reflected off of earth's atmosphere back down to the surface) is correct about greenhouse effect.
For the greenhouse effect to occur, greenhouse gas molecules are mostly needed. Examples of these gases include:
--> Carbon dioxide (CO2),
--> Water vapor (H2O), and
--> Methane (CH4)
Over the years, the excessive human activities has lead to increase in the greenhouse gas molecules which has negatively affected the greenhouse effects.
Answer:

Explanation:
Using the conservation of energy we have:

Let's solve it for v:

So the speed at the lowest point is 
Now, using the conservation of momentum we have:

Therefore the speed of the block after the collision is 
I hope it helps you!
ANSWER - (1) are constantly moving (2) have volume (3) have intermolecular forces (4) undergo perfectly elastic collisions (5) have an average kinetic energy proportional to the ideal gas’s absolute temperature
<span><span>A. </span>Length: km<span>
The Si units of all the left measurements are true thus, in length the typical
and standard SI unit is meter. SI units, also called as International Standard
of Units, is composed of the following systematized units of physical measure
which include, mole (amount of substance), candela (luminous intensity), kelvin
(temperature), ampere (electric current), second (time), kilogram (mass), and meter
(length). Hence, these measures spheres in multiplication or division by power
of 10, increase or decrease in measure.</span></span>