I think c .. I already took a course .. and the test had that question.. I cant remember the answer though
        
                    
             
        
        
        
No that's as low as it goes 
        
                    
             
        
        
        
Answer:
let the number of cows = x 
let the number of chickens = y
since there are 42 heads: 
x + y = 42
and since a cow has 4 legs, and a chicken has 2 
4x + 2y = 144
from first equation: 
x + y  = 42 
x = 42 - y (now, we will substitute this in the second equation)
4(42 - y) + 2y = 144 
168 - 4y + 2y  = 144
2y = 168 - 144 
2y = 24 
y = 12
now, we know the number of chickens. we will replace y with 12 in the first equation since it is more simpler 
x + 12 = 42
x = 30
So, there are 30 cows and 12 chickens 
Brainly it if you find the answer helpful 
 
        
             
        
        
        
Answer:
D   pi/4, 3pi/4
Step-by-step explanation:
Differentiate the function then equal it to zero and solve for the interval (see attached workings)