Answer:
70 
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
28
Step-by-step explanation:
So its a 50/50 chance for the coin to land on heads or tails, so we would divide 56 by 2
56/2 = 28
 
        
             
        
        
        
Answer:
10⁴ seconds
Step-by-step explanation:
Given that,
A person breathes  in about cubic meters of air per second.
 in about cubic meters of air per second.
We need to find time taken to breathe 2.5 cubic meters of air.
In 1 sec =  m³ of air breathe
 m³ of air breathe
Let in x seconds, 2.5 m³ of air taken by the person.

Hence, in 10⁴ seconds 2.5 m³ of air is taken by the person.