The contact force is indeed caused by "Contact". 
Air resistance is basically a type of friction, which is apparently present providing two object contact.
The rest selections are all interaction force, which is not necessarily caused by contact.
        
                    
             
        
        
        
They expend more oxygen. Littler endotherms lose warmth to the earth proportionately speedier than huge endotherms: less warm mass, protecting layers in littler creatures are less successful by dint of being more slender, and more prominent surface region to volume proportion implies snappier radiation of warmth
        
             
        
        
        
Get To Safety And Call A Fire Department, 
Be Alert Of The Signals Of The Presence Carbon Monoxide
Get Routine Checks Of Security Tools
 
        
             
        
        
        
5.6 which would be acidic!