D, all apply
You can cut all in half and they will be equal
        
                    
             
        
        
        
Absolute value of -1/3 is 1/3
        
             
        
        
        
Answer:
my answer in the paper
don't forgotten for press "love"
 
        
                    
             
        
        
        
Answer:  see proof below
<u>Step-by-step explanation:</u>
Given: cos 330 = 
Use the Double-Angle Identity: cos 2A = 2 cos² A - 1

Proof LHS → RHS:
LHS                          cos 165
Double-Angle:        cos (2 · 165) = 2 cos² 165 - 1
                              ⇒ cos 330 = 2 cos² 165 - 1
                              ⇒ 2 cos² 165  = cos 330 + 1
Given:                        
                               
Divide by 2:               
                              
                              
 
Square root:             
Scratchwork:            
                              
              Since cos 165 is in the 2nd Quadrant, the sign is NEGATIVE
                              
LHS = RHS 
 
        
             
        
        
        
your answer is 
b = 15 pi
length of ypx = circumfrance of circle - 1/4 of circumfrance of circle
= 2pi r - 2pi r/4 = 6 pi r / 4 = 3 pi r / 2
= 3 pi × 10/2 = 15 pi