The answer is destructive interference. You have this for both C and D. I suspect one of C or D is supposed to be constructive interference... But destructive interference is the answer
Answer:
D= 1999.2 m
Explanation:
Given that
Average velocity ,v= 0.98 m/s
time ,t= 34 min
We know that
1 min = 60 s
That is why
t= 34 x 60 =2040 s
We know that
Displacement = Average velocity x time
D= v t
Now by putting the values in the above equation
D= 0.98 x 2040 m
D= 1999.2 m (eastward)
The direction of the displacement will be towards eastward.
That is why the displacement will be 1999.2 m or we can say that 1.9992 km.
Let us consider the tension produced on both the sides of the rope is T.
We have been given that the rope is mass less and the rope is passing through a pulley which is stationary.



The body is moving downward with an acceleration of 
As the rope is the same one which is passing over a mass less pulley and connected by two masses,hence, acceleration of each block will be the same in magnitude.

Here the tension is acting in vertical upward direction and the weight is acting in vertical downward direction. Here,the body is moving in vertical upward direction. Hence, the net force acting on it is-
[1]

Here the tension is acting in vertical upward direction while weight is in vertical downward direction. The body is moving in downward direction. Hence the net force acting on it will be-
[2]
Combing 1 and 2 we get-


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![[m_{2} -m_{1} ]g=a[m_{1}+ m_{2}]](https://tex.z-dn.net/?f=%5Bm_%7B2%7D%20-m_%7B1%7D%20%5Dg%3Da%5Bm_%7B1%7D%2B%20m_%7B2%7D%5D)
![[4.5-m_{1}]g =\frac{3}{4}g[4.5+ m_{1}]](https://tex.z-dn.net/?f=%5B4.5-m_%7B1%7D%5Dg%20%3D%5Cfrac%7B3%7D%7B4%7Dg%5B4.5%2B%20m_%7B1%7D%5D)
![4[4.5-m_{1}] =3[4.5+m_{1} ]](https://tex.z-dn.net/?f=4%5B4.5-m_%7B1%7D%5D%20%3D3%5B4.5%2Bm_%7B1%7D%20%5D)

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