1. Air pollution is a problem<span> because it can cause damage to animals, trees, plants, crops and water sources in the environment. </span>Pollution<span> in the </span>air<span> causes </span>problems<span> for aviation because it reduces visibility, while also being responsible for damaging buildings and other structures.
2. </span><span>The air we breathe has a very exact chemical composition; 99 percent of it is made up of nitrogen, oxygen, water vapor and inert gases. Air </span>pollution occurs<span> when things that aren't normally there are added to the air. A common type of air </span>pollution<span>happens when people release particles into the air from burning fuels.
3. </span>Pollution prevention (P2) is any practice that reduces, eliminates, or prevents pollution at its source. ... Reducing the amount of pollution produced means less waste to control, treat, or dispose of. Less pollution means less hazards posed to public health and the environment.
4. Why is it so important to have clean air?
The moon is made up mostly of Silicates, hope this answer helps.
Answer:
Explanation:
Given
height of grand canyon is 
Rock is dropped i.e. initial velocity is zero

Using Equation of motion

h=height
u=initial velocity
a=acceleration
t=time
here a=acceleration due to gravity


There's no such thing as "an unbalanced force".
If all of the forces acting on an object all add up to zero, then we say that
<span>the group </span>of forces is balanced. When that happens, the group of forces
has the same effect on the object as if there were no forces on it at all.
An example:
Two people with exactly equal strength are having a tug-of-war. They pull
with equal force in opposite directions. Each person is sweating and straining,
grunting and groaning, and exerting tremendous force. But their forces add up
to zero, and the rope goes nowhere. The <u>group</u> of forces on the rope is balanced.
On the other hand, if one of the offensive linemen is pulling on one end of
the rope, and one of the cheerleaders is pulling on the other end, then their
forces don't add up to zero, because even though they're opposite, they're
not equal. The <u>group</u> of forces is <u>unbalanced</u>, and the rope moves.
A group of forces is either balanced or unbalanced. A single force isn't.
<span>The question says: complete the sentence: The distance between stars is typically measured in.... The answer is 'light years" - the distance that light travels in a year. That's because it's a very big unit and if we were using smaller units, we would be using huge numbers that would be hard to read and would take up a lot of space.</span>