Answer:
First, as you may know, the light travels at a given velocity.
In vaccum, this velocity is c = 3x10^8 m/s.
And we know that:
distance = velocity*time
Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.
This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)
Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.
Answer: Depends
Explanation:
Depends on how much the diver weighs.
Hello there!
I hope you and your family are staying safe and healthy during this unprecendented time.
A) What is the work done?
Answer: We need to use the formula



B) What is the work done on the cart by the gravitational force?
Alright, we know that the gravitional force is perpendicular to the diplacement. Therefore, we gonna use the following formula:


C) What is the work done on the cart by the shopper?
This is the easier part, since we already know that the work done by the shopper is the same as the work done by the friction force

D) Find the force the shopper exerts, using energy considerations.

E) What is the total work done?
You just need to add them:

Answer:
4948020
Explanation:
(6.9*10-6)(770*102)
<u>Multiply 6.9 by 10
.
</u>
(
69
−
6
)
(
770
⋅
102
)
<u>Subtract 6 from 69
.
</u>
63
(
770
⋅
102
)
<u>Multiply 770 by 102
.
</u>
63
⋅
78540
<u>Multiply 63 by 78540
.
</u>
4948020