InterviewSolution
 Saved Bookmarks
    				| 1. | 
                                    Why is helium gas is used in hot air balloon? | 
                            
| 
                                   
Answer»  Answer: While hot air balloons rely on on BOARD burners to HEAT up air in ORDER to generate lift, gas balloons are FILLED with a gas (helium or HYDROGEN) that is lighter than air, therefore providing lift. ...  | 
                            |