The word "static" would be known to be friction as air rushing against an airplane
        
             
        
        
        
Monoammonium phosphate effectively smothers the fire, while sodium bicarbonate induces a chemical reaction which extinguishes the fire. Fire extinguishers with a Class C rating are suitable for fires in “live” electrical equipment.
 
        
                    
             
        
        
        
The ions are in fixed positions.
Explanation:
Ionic solids are poor conductors of electricity because their ions are fixed in position. Their ions are not free to move about. They are fixed in crystal lattices. 
- For the conduction of electricity, compounds must possess free mobile electrons and moving ions in solution. 
- Ionic compounds are formed by the electrostatic attraction between a metallic and non-metallic ion. 
- They actually contain ions but their ions are locked up. 
- They are not free to move about. 
- Electrical conduction involves ion mobility. 
- In molten and aqueous forms, they are able to conduct electricity because their ions are then mobile. 
learn more: 
Ionic compound brainly.com/question/6071838
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Work = (force) x (distance)
The worker does  (40N) x (4m) = 160 joules of work.
Friction eats up    (27N) x (4m) = 108 joules of that energy, 
                                                         generating 108  joules of heat.                          
The remaining    (160J - 108J) = 52 joules of energy moves the box.