Answer:
Chemical, mechanical, thermal i guess
A is not the correct answer because the amplitude and oscillation and there is 1/2 A in oscillation
Use conservation of momentum ;
m1u1 + m2u2 = m1v1 + m2v2
1200×15.6 + 0 = 2700v
v = 18720/2700
v = 6.933 or ~ 7 m/s
Explanation:
It is given that,
Wavelength, 
Slit width, 
Order, m = 2
If the diffracted light projects onto a screen at distance 1.50 m, L = 1.5 m
For the diffraction of light,


y = 0.0037 m
So, the distance from the center of the diffraction pattern to the dark band is 0.0037 meters. Hence, this is the required solution.
Condensation.
Would be the right answer.