Answer:
A nuclear winter is a climatic phenomenon that would follow the detonation of several atomic bombs in the event that a nuclear war broke out. These bombs would cause firestorms that would raise smoke, dust and particles into the atmosphere that would end up in the stratosphere and eventually spread throughout the globe.
Explanation:
That idea is far fetched, because even though those same particles would absorb sunlight, it would raise the temperature in the stratosphere and cause a decrease in temperature in the Earth's layer. Unable to seep the sun's rays, many plant species would die and this would affect the entire food chain.
In addition, that temperature rise in the stratosphere would destroy part of the ozone layer, causing greater exposure to ultraviolet rays. This would end up affecting health and further damaging plant species.
Answer:
7. Net constant force down the ramp
Explanation:
After the car is released and starts moving up the ramp, the only force that is applied on the car is weight because of the gravity, we were told that the friction force is neglected. the force because of the weight is given by:

where θ is the angle of the ramp.
as you can see those values won't change, so the force remains constant down the ramp.
The idea that "students ' immune systems have declined due to the use of hand sanitizers " is a hypothesis.
The term hypothesis refers to an intelligent guess or idea often based which is subject to scientific investigation via experiments.
A hypothesis may be right or wrong. We can only prove a hypothesis by subjecting it to a series of rigorous experiments.
Thus Collette's idea is a hypothesis.
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