Answer:
You got it right. Triangle DAC
Step-by-step explanation:
Line segment DA is a perpendicular bisector(it cuts line segment CE perfectly in half making line segment AE an CA congruent. Since the triangle share line segment DA that makes them congruent by the SAS postulate 
 
        
             
        
        
        
GP = 1/2 , 1/4 , 1/8 , 1/16
1st) the common ratio is (1/4 : 1/2 ) = 1/2, so r =1/2
2nd) the sum of a GP is:
S= a(1-rⁿ)/(1-r)
S=(1/2).[1-(1/2)⁴]/(1-1/2) = 15/16
        
                    
             
        
        
        
Step-by-step explanation:
"identity" means an operation that does nothing.
For adding numbers, adding 0 changes nothing, so 0 is the identity for addition.
For multiplication, multiplying by 1 changes nothing, so 1 is the identity for multiplication.
 
        
             
        
        
        
Answer: Estimates vary, but each person uses about 80-100 gallons of water per day
 
        
             
        
        
        
Answer:
the third one is the correct answer