Answer:
   37.7 mi²/h
Step-by-step explanation:
The area formula is ...
   A = πr²
Differentiating with respect to time gives ...
   dA/dt = 2πr·dr/dt
Filling in the given values, we have ...
   dA/dt = 2π(3 mi)(2 mi/h) = 12π mi²/h
The area is increasing at the rate of about 37.7 mi² per hour.
 
        
             
        
        
        
Answer: -1/5
Step-by-step explanation:
14/20 - 81/90=
7/10-9/10=       ==> 10 is the GCF of 20 and 90
(7-9)/10=
-2/10=-1/5
 
        
                    
             
        
        
        
<span>Hi, A cylinder has 3 faces - 2 circle ones and a rectangle</span>
        
                    
             
        
        
        
Answer:
  hrs/house
hrs/house 
Step-by-step explanation:
 Rate is the amount of work done per unit of time;
   Let Cara's rate  = C
    Let Jena's rate  = J 
         C + J  = 4  ------ i 
Now;
   Working alone:
              Jena takes twice as long as Cara
                           J  = 2C  ---- i 
How long does it take Cara to clean a house alone 
            C + J  = 4 
              J = 2C 
         C + 2C = 4 
            3C = 4 
               C =  hrs/house
hrs/house 
 
        
             
        
        
        
I am sure the correct answer is x=0.38629436…hope this help you