I think it is d I hope this help you if not let me know if it is not right
Answer:
Rs. 432*10^3 (In kilowatts per hour)
I hope it will be useful.
Yes, this is correct Answer.
The question for this problem would be the minimum headphone delay, in ms, that will cancel this noise.
The 200 Hz. period = (1/200) = 0.005 sec. It will need to be delayed by 1/2, so 0.005/2, that is = 0.0025 sec. So converting sec to ms, will give us the delay of:Delay = 2.5 ms.