The answer is A, it breaks down and releases thermal energy.
Answer:

Explanation:
When a standing wave is formed with six loops means the normal mode of the wave is n=6, the frequency of the normal mode is given by the expression:

Where
is the length of the string and
the velocity of propagation. Use this expression to find the value of
.

The velocity of propagation is given by the expression:

Where
is the desirable variable of the problem, the linear mass density, and
is the tension of the cord. The tension is equal to the weight of the mass hanging from the cord:

With the value of the tension and the velocity you can find the mass density:


600 watts may be your answer:)
C. is the only double reaction here given that a double replacement reaction involves two compounds that exchange previous components, and C is the only solution with two compounds present