Answer:
382Hz
Explanation:
The question lacks the required option. Find the complete question in the attachment.
The long organ pipe open at both ends is called an open pipe. The fundamental frequency for an open pipe is expressed as F0 = V/2L
Harmonics are integral multiples of the fundamental frequency. For open pipes its harmonics are 2fo, 3fo, 4fo, 5fo...
Given fundamental frequency f0 to be 85 Hz, the following frequencies will be present as a standing wave;
First overtone f1 = 2fo = 2(85) = 170Hz
Second overtone f2 = 3fo = 3(85) = 255Hz
Third overtone = 4fo = 4(85) = 340Hz
Based on the option it can be seen that the only frequency that is not present as a standing wave is 382Hz
