Answer: You don't do work.
Explanation: If you don't do the work you don't have to ask this question. With work comes labor. With labor comes change. With change comes resistance and people do not like change. IT causes anger, so if you stop doing work and stick to the important supply like food, water, and shelter you don't have to go through the trouble of this and we can live in a peaceful environment for this world to be better than it is. People do to much, it's a natural fact but you can change the entire picture. If you read all of this thank you for accepting the fact of life.
Answer:
a) 



b) 
Explanation:
From the exercise we got the ball's equation of position:

a) To find the average velocity at the given time we need to use the following formula:

Being said that, we need to find the ball's position at t=2, t=2.5, t=2.1, t=2.01, t=2.001



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b) To find the instantaneous velocity we need to derivate the equation


Can you translate to english ?
Answer:
t = 11.1 hours
Explanation:
The question says that, "A mobile advances at 20 m / s and travels a distance of 800 km. Determine the time in hours you use".
Given that,
Speed of a mobile, v = 20 m/s = 72 km/h
Distance, d = 800 km
We know that,
Speed = distance/time
So,

So, it will take 11.1 hours.