Ok so this can get tricky, it is basically just asking for you to perform many unit conversions. I'll try to simplify it for you here while still maintaining the explanation. If you have any questions about this process feel free to message me. 
3 yards = ____ miles (conversion factor is 1760 because there are 1760 yards in a mile) 
3/1760 = 0.017 miles,
Now we just need to convert seconds to hours. 
1 second is how many mins, then how many mins in an hour? 
360 seconds in an hour. 
Ok now we just need to combine these two pieces of info, 
0.017/360 = 4.72222 miles per hour. Thus 4.72 is the answer.
        
                    
             
        
        
        
Answer:
The answer is B 300 sq. ft.
Step-by-step explanation:
If you multiply 15 by 2 you were to get 30 but since it is 15 multiplied by 20 instead its like adding a 0 at the end of the number so we change 30 to 300. 
Hope this helps :)
 
        
                    
             
        
        
        
Answer: there would be 30 chairs
Step-by-step explanation:6 times 5 is 30. 
 
        
                    
             
        
        
        
You would need a rainbow shape ruler to answer these angles/degrees
        
                    
             
        
        
        
Answer:
(1,3)
Step-by-step explanation: