A drainage pipe running under a freeway is 28.0 m long. Both ends of the pipe are open, and wind blowing across one end causes the air inside to vibrate. Part A If the speed of sound on a particular day is 340 m/s , what will be the fundamental frequency of air vibration in this pipe? Express your answer with the appropriate units. Activate to select the appropriates template from the following choices. Operate up and down arrow for selection and press enter to choose the input value typeActivate to select the appropriates symbol from the following choices. Operate up and down arrow for selection and press enter to choose the input value type f = nothing nothing Request Answer Part B What is the frequency of the lowest harmonic that would be audible to the human ear? (The lowest frequency we can hear is about 20 Hz .) Express your answer with the appropriate units. Activate to select the appropriates template from the following choices. Operate up and down arrow for selection and press enter to choose the input value typeActivate to select the appropriates symbol from the following choices. Operate up and down arrow for selection and press enter to choose the input value type f = nothing nothing Request Answer Part C What will happen to the frequency in the later afternoon as the air begins to cool? increase decrease