Answer:
What do I have to do?? I don't understand
 
        
             
        
        
        
Use the rule of 3 simple 
1680 beats ------- 60 min.
x beats -------------- 1 min. 
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 x = (1680*1)/60 = 1680/60 = 168/6 = 28 beats per minute 
hope helped 
        
             
        
        
        
Answer:
I dont remember how to do this but i wish you luck, try searching on khan academy for how to do this ;)
Step-by-step explanation:
 
        
             
        
        
        
-18 negative eighteen
6 positive six
12 positive twelve
-40 negative forty
        
             
        
        
        
Answer: wouldn't be 1608.5? let me know if im wrong.
V = πr^2 h= π · 8^2 · 8 ≈ 1608.49544