Answer:
The index of refraction of the second medium is higher.
Step-by-step explanation:
 
        
                    
             
        
        
        
X=300. basically multiply 150 times 2 to get the number. To check if it’s right divided 300 by 2 and see if it’s 150 or not. If not Choose another number
        
             
        
        
        
So what u do is divide 400 by 8 and then you will have yuor answer
        
                    
             
        
        
        
Answer:  169.2 per acre are produced if a field is in the top 25%.
Step-by-step explanation:
Given:  The mean rain-fed corn yield of harvested fields are normally  distributed, produce 147.2 bushels per acre with a standard deviation of 33 bushels per acre.
Let X denote the mean rain-fed corn yield of harvested fields.
Let x denotes the number of bushels per acre are produced if a field is in the top 25%.
Top 25% on a density curve means , (100-25%)i.e. 75% area lies below x.
I.e.
  .
.
Z-score for p-value of 0.75 (one tailed)=0.67 [By z-table]
Then, 

Here approx value is 169.2 (from options).
So, 169.2 per acre are produced if a field is in the top 25%.