The answer is true...............
Answer:
(a) Ratio of mean density is 0.735
(b) Value of g on mars 0.920 
(c) Escape velocity on earth is 
Explanation:
We have given radius of mars
and radius of earth 
Mass of earth 
So mass of mars 
Volume of mars 
So density of mars 
Volume of earth 
So density of earth 
(A) So the ratio of mean density 
(B) Value of g on mars
g is given by 
(c) Escape velocity is given by

A vacuum is an electrical motor and<span> which it converts electrical energy into mechanical energy.
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First, let's express the movement of Car A and B in terms of their position over time (relative to car B)
For car A: y=20x-200 Car A moves 20 meters every second x, and starts 200 meters behind car B
For Car B: y= 15x Car B moves 15 meters every second and starts at our basis point
Set the two equations equal to one another to find the time x at which they meet:
20x - 200 = 15x
200 = 5x
x= 40
At time x=40 seconds, the cars meet. How far will Car A have traveled at this time?
Car A moves 20 meters every second:
20 x 40 = 800 meters