Given that the depth varies directly with amount of rainfall, then we shall have:
let d be the depth and r be the rainfall amount
dαr
thus
d=kr
where, k is the constant of proportionality, thus the formula will be:
d=kr
        
             
        
        
        
I think the answer is one. 
I think this because since it’s times you would do backwards and divide 0.89 divided by 0.89 and you would get 1. I hope I’m correct sorry if I’m not.
        
                    
             
        
        
        
Answer: 0.12
Explanation:
3/25 = 0.12
        
                    
             
        
        
        
The simplified form of R(x) is 
<h3>Simplifying an expression </h3>
From the question, we are to simplify the expression 
From the given information, 

and 

Also,

∴ 

Factoring each of the quadratics 



Simplifying




Hence, the simplified form of R(x) is 
Learn more on Simplifying an expression here: brainly.com/question/1280754
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