This
 is
 true 
Electromagnetic waves travel fastest through vacuum
        
             
        
        
        
Answer: True
Explanation: Following are the properties that are used to identify minerals:
(1) Color
(2) Hardness
(3) Magnetism : It is the property of mineral to attract or repel with other magnetic materials.
(4) Luster : It is the property that shows the surface is reflecting light or not. 
(5) Reactivity: Reactivity is also responsible to identify mineral. How the mineral is reacting with acids, bases etc helps to identify type of minerals.
 
        
                    
             
        
        
        
Answer:
electrons neutrons and protons
Explanation:
electron are negative
nuetron are neutral
protons are positive
 
        
             
        
        
        
Answer:
 0 N.
Explanation:
Force: This can be defined as the product of mass and the acceleration of the body. The S.I unit of force is Newton (N).
The expression of net force when both force act in the different direction is given as
F' = W-F ........................ Equation 1
Where F' = Net force on the bag, W = gravitational force on the bag, F = Force acting upward on the bag
Given: W = 18 N, F = 18 N.
Substitute into equation 1
F' = 18-18
F' = 0 N.
Hence the net force = 0 N.