Inside the bar magnet, the magnetic field points from north to south. Statement A is correct.
Magnetic Field:
It is defined as a vector field or the influence of the magnet on the electric current, charges and ferromagnetic substance.
The strength of magnetic field is depends up on the numbers of magnetic field lines per unit area.
- Magnetic field lines emerge from the North pole and end in the South pole of a bar magnet. 
- Inside the magnet are also present inside the bar magnet and never intersect at any point.
Therefore, inside the bar magnet, the magnetic field points from north to south.
To know more about Magnetic Field:
brainly.com/question/19542022
 
        
                    
             
        
        
        
 
 

 When an opaque obstacle is placed between a source of light and a screen, a shadow of the obstacle is formed on the screen. The kind of shadow depends on the size of the source of light. In other words, the earth casts its shadow on the moon. The solar eclipse occurs when the moon comes between the sun and the earth.
When an opaque obstacle is placed between a source of light and a screen, a shadow of the obstacle is formed on the screen. The kind of shadow depends on the size of the source of light. In other words, the earth casts its shadow on the moon. The solar eclipse occurs when the moon comes between the sun and the earth.
 
 
        
                    
             
        
        
        
Yo sup??
since the collision is elastic therefore we can say that the two balls will then move in opposite direction.
If ball 1 was moving from east to west then after collision it will move from west to east 
and if ball 2 was moving from west to east then it will start moving from east to west.
Hope this helps.
 
        
             
        
        
        
Answer:
1 Frequency
2 Wavelength
3 Amplitude
4 Crest
Hope it helps pls mark brainliest