Answer:

Explanation:
Total internal reflection can happen when light goes from a medium with higher refractive index (in this case, glass) to a medium with lower refractive index (in this case, water).
Snell's Law tells us that 
, where the <em>i</em> stands for incident (in this case, glass) and the <em>r</em> for refracted (in this case, water). We want to know when 
, that is, when 
, and this happens when the incident angle is:

Which for our values means:

 
        
             
        
        
        
Answer:
  y₀ = 1020.3 m
Explanation:
This is a projectile launching exercise, in this case as the package is released its initial vertical velocity is zero.
             y = y₀ + 
 t - ½ g t²
when it reaches the ground its height is zero
            0 = y₀ + 0 - ½ g t²
            y₀ = ½ g t²
            
let's calculate
          y₀ = ½ 9.8 14.43²
          y₀ = 1020.3 m
 
        
             
        
        
        
Answer:
In terms of distance, average speed is 20 km/h
In terms of displacement, average speed is 0 km/h.
Explanation:
Total distance:

Total time is 3.0 hours
but:

In terms of distance.
substitute:


In terms of displacement:

 
        
             
        
        
        
I think its true i dont kno for sure
        
             
        
        
        
The best answer would be the 4th choice. "They help scientists explain concepts that are difficult to observe, this also covers the first answer which helps the scientist to answer complex questions. A scientific model is not used prove scientific laws as they may not always have all the data to prove so, instead it is used to allow them to explain better concepts revolving around science through research and may also allow them to predict results based on the accumulation of data and analyzing the trend of this resulting information.