Answer:

Explanation:
Given that,
Lightning flashes one mile (1609 m) away from you.
We need to find the time it take the light to travel that distance. Let the time be t. We know that,
speed = distance/time

So, the required time is 
Social perception (or person perception) is the study of how people form impressions of and make inferences about other people as sovereign personalities.A real-world example of social perception is understanding that others disagree with what one said when one sees them roll their eyes.
The answer is:
Forces acting on the sled are paired with equal and opposite forces.
The explanation:
About to push you, this means that he doesn't push yet. If the sled is on level ground and no one is pushing it, then forces are equal and opposite.
The gravity force pulls down and the ground pushes up.
This is Newton's third law:
Newton's third law: If an object A exerts a force on object B, then object B must exert a force of equal magnitude and opposite direction back on object A.
This law represents a certain symmetry in nature: forces always occur in pairs, and one body cannot exert a force on another without experiencing a force itself.
We can also see Newton’s third law at work by taking a look at how people move about. Consider a swimmer pushing off from the side of a pool.
Answer:
Part a)

Part b)

Part c)

Part d)

Part e)

Part f)

Explanation:
As we know that initial velocity of the ball is given as


Now final velocity of the system is given as

Part a)
now magnitude of initial momentum is given as



Part b)
Change in momentum is given as



Part c)
As we know that average force is defined as the rate of change in momentum
so here we have



Part d)
Magnitude of change in momentum is given as



Part e)
As we know that in 2nd case the force is same as the initial force
so we will have



Part f)
Since this is elastic collision so change in kinetic energy must be ZERO
