Answer: verb
Explanation: you can reiterate an idea, doing so is an action
 
        
             
        
        
        
I think you need to show the passage first to get ur answers
        
                    
             
        
        
        
It is 4. because it says in the paragraph and I quote: "helium has a very low density. it is used in daily weather balloons to carry instruments that record, tempature, humidy, and pressure readings in the atmosphere.