The answer to your quesiton is,
A) Venus has phases.
-Mabel <3
 
        
                    
             
        
        
        
Answer: The center of gravity is 1.1338 m away from the left side of the barbell
Explanation:
Length of the barbell = 1.90 m
The distance center of gravity from left = x
Mass on the left side = 25 kg
The distance center of gravity from right = 1.90 - x
Mass on the right side = 37 kg
At the balance point: 


The center of gravity is 1.1338 m away from the left side of the barbell
 
        
                    
             
        
        
        
Answer:
It's an Angle of incidence that provides a 90° angle but is also refracted at the same time. it's used to find the water-air boundary (which is 48.6 degrees). in addition, its an angle of incidence value. 
 
        
             
        
        
        
I think iron? i’m not 100% sure