Answer:
toward the normal
Explanation:
Light travels at different speed in different mediums.
Refractive index is equal to velocity of the light 'c' in empty space divided by the velocity 'v' in the substance.
Or ,
n = c/v.
Light travels at a slower speed in water as compared to air because there are more number of interfering molecules in the path of the light in case of water as compared to liquid.  
When a light travels from lower denser medium say water to higher denser medium say water, it bends towards the perpendicular (normal) as its speed reduces in that medium.
  
        
             
        
        
        
As we sit in a chair, Action force will be only in one direction and that direction would be downward only.
In short, Your Answer would be Option A
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Answer:1.084
Explanation:
Given
mass of Pendulum M=10 kg
mass of bullet m=5.5 gm
velocity of bullet u
After collision let say velocity is v
conserving momentum we get


Conserving Energy for Pendulum
Kinetic Energy=Potential Energy

here  from diagram
 from diagram
therefore 

initial velocity in terms of v

For first case 

for second case 

Therefore 


i.e.
 
        
             
        
        
        
D.) It is an "Element".
[ Element cannot be separated by any means ]
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