Answer: 
Teachers to Students: 1:9, 1 to 19, 1/19
Students to teachers: 19:1, 19 to 1, 19/1
(If this is wrong the answers might be different for you but this is what I got an I was right)
 
        
             
        
        
        
Answer:
5/18
Step-by-step explanation:
speed = distance / time
s = (2/9 miles) / (4/5 hours)
To divide by a fraction, multiply by the reciprocal:
s = (2/9) × (5/4)
s = 10/36
s = 5/18
So the snake's speed is 5/18 miles per hour.
 
        
             
        
        
        
Answer:
-1.8f - 19
Step-by-step explanation:
 
 
        
             
        
        
        
Yes since the four sides are always parallel in a square <span />
        
                    
             
        
        
        
Answer:
191
Step-by-step explanation:
The amount spent for a single text:  177/17,7=0,1
x×0,1=19,1
x=19,1/0,1
x=191