Answer:
B 
the humidity is the % of water in the air and it is out of 100% of the air. so 10/100 is low
 
        
                    
             
        
        
        
Now I'm just going to assume you mean Charles law. So when working with gases, there are 4 properties: pressure, volume, temp, and quantity. The simple gas laws deal with 2, while leaving the other 2 constant. If Charles' Law changes temp and volume, what 2 stay constant? Pressure and quantity
        
             
        
        
        
The reaction will be: FeBr2 + K --> KBr + Fe
Balancing gives: FeBr2 + 2K --> 2KBr + Fe
The molar mass of FeBr2 is 55.85 + 2*79.9 = 215.65 g/mol.
We divide 40 g / 215.65 g/mol = 0.185 mol FeBr2
Based on stoichiometry:
(0.185 mol FeBr2)(2 mol KBr/1 mol FeBr2) = 0.370 mol KBr
        
             
        
        
        
3 *0.75 = 2.25 mol that’s is ur answer for this question
        
             
        
        
        
Answer:
12345678909ygtufyghkkgjfjvhbkjn,bhmgncfxcgvhbm
Explanation: