Answer:
I think the answer is 0
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
2.4 hours 
Step-by-step explanation:
Get common denominators - 
1/12 x 5/5 = 5/60
1/5 x 12/12 = 12/60
 The turtle walks ata 5/60 a kilometer an hour. 
divide remaining time by 5/60
(12/60) / (5/60) = 2.4 hours 
 
        
                    
             
        
        
        
Step-by-step explanation:
2tan 30° / 1 + tan² 30° =
2(⅓√3) /1 + (⅓√3)² =
⅔√3 / 1+ ⅓ =
⅔√3 / 4/3 =
2/4 √3 =
½√3 = sin 60° (proven)
 
        
             
        
        
        
To do it without a calculator:
10% of 67 is 6.7
6.7 x 8 is 53.6 (80%)
1% of 67 is .67
53.6 - .67 is 52.93 (79%)