The answer of this is C!!!
        
             
        
        
        
Because Mars is too far away for its gravitational pull to affect us, in addition Earths gravitational pull is greater than Mars anyways. 
        
             
        
        
        
Answer:
The maximum speed of sonic at the bottom of the hill is equal to 19.85m/s and the spring constant of the spring is equal to (497.4xmass of sonic) N/m
Energy approach has been used to sole the problem. 
The points of interest for the analysis of the problem are point 1 the top of the hill and point 2 the bottom of the hill just before hitting the spring
The maximum velocity of sonic is independent of the his mass or the geometry. It is only depends on the vertical distance involved
Explanation:
The step by step solution to the problem can be found in the attachment below. The principle of energy conservation has been applied to solve the problem. This means that if energy disappears in one form it will appear in another. 
As in this problem, the potential and kinetic energy at the top of the hill were converted to only kinetic energy at the bottom of the hill. This kinetic energy too got converted into elastic potential energy . 
x = compression of the spring = 0.89
 
        
             
        
        
        
Answer:

Explanation:
From the question we are told that:
Mass 
Drop distance 
Generally the equation for Spring Constant is mathematically given by
  
  
  
 
        
             
        
        
        
Answer:
1. 1. A quantity is completely described by magnitude alone. A quantity Is completely described by a magnitude with a direction.
[a]. scalar, vector
b. vector, scalar
2.2. Speed is a velocity is a quantity and quantity.
a. scalar, vector
[b]. vector, scalar