Answer:
a) 
b)
c) 
d) Treat the humans as though they were points or uniform-density spheres.
Explanation:
Given:
- mass of Mars,

- radius of the Mars,

- mass of human,

a)
Gravitation force exerted by the Mars on the human body:

where:
= gravitational constant


b)
The magnitude of the gravitational force exerted by the human on Mars is equal to the force by the Mars on human.


c)
When a similar person of the same mass is standing at a distance of 4 meters:


d)
The gravitational constant is a universal value and it remains constant in the Universe and does not depends on the size of the mass.
- Yes, we have to treat Mars as spherically symmetric so that its center of mass is at its geometric center.
- Yes, we also have to ignore the effect of sun, but as asked in the question we have to calculate the gravitational force only due to one body on another specific body which does not brings sun into picture of the consideration.
Answer: 20.4 miles
Explanation:
Here we need to use the equation:
Velocity = Distance/Time.
Initially we have that he can travel 30 miles in 2 hours, so the velocity is:
V = 30mi/2h = 15mph
Now, we reduce the velocity by 3 mph, so the new velocity is 15mph - 3 mph = 12mph.
Now we want to know the distance traveled in 1.7 hours with this velocity, this is.
Velocity*Time = Distance
12mi/h*1.7h = 20.4 miles
It spins one bc it takes 365 days to make a year and to make a year the earth has to mov some
For this case, the switch is located at point B of the diagram.
Remember that point D is the universal symbol for resistance.
In A what you have is a source of power and in C what you have is a cable.
Therefore, the answer for this case is B.