That's up to you because you have to go through the book to see their expressions
        
             
        
        
        
Explanation:
Below is an attachment containing the solution. 
 
        
             
        
        
        
Answer:

Explanation:
R = Horizontal range of projectile = 75 m
v = Velocity of projectile = 37 m/s
g = Acceleration due to gravity = 
Horizontal range is given by

The angle at which the arrow is to be released is  .
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Answer:
 R_cm = 4.66 10⁶ m
Explanation:
The important concept of mass center defined by
          R_cm = 1 / M   ∑  x_i m_i
where M is the total mass, x_i and m_i are the position and masses of each body
Let's apply this expression to our case.
Let's set a reference frame where the axis points from the center of the Earth to the Moon,
        R_cm = 1 / M (m_earth 0 + m_moon d)
the total mass is
       M = m_earth + m_moon
      
the distance from the Earth is zero because all mass can be considered to be at its gravimetric center
let's calculate
       M = 5.98 10²⁴ + 7.35 10²²
       M = 6.0535 10₂⁴24 kg
we substitute
       R_cm = 1 / 6.0535 10²⁴ (0 + 7.35 10²² 3.84 )
       R_cm = 4.66 10⁶ m
 
        
             
        
        
        
Im pretty sure its C- Wavelength