R= diameter/2 
answer: 8 units
        
             
        
        
        
Answer:
Yeah I would be too
Step-by-step explanation:
 
        
             
        
        
        
Answer:
7n = 12+ 3n
Step-by-step explanation:
The first thing to do is subtract 3n from 7n. This would get you 4n = 12. 4 times 3 equals 12, so n equals 3. 
To check your answer. 21 = 12+9. sure enough it matches our answer
 
        
             
        
        
        
Answer:
the answer to (8.4 × 102) (2.5 × 106) = 227,052