Consult Multiple-Concept Example 3 for background pertinent to this problem. A speaker has a diameter of 0.30

Question:

Consult Multiple-Concept Example 3 for background pertinent to this problem. A speaker has a diameter of 0.30 m.
(a) Assuming that the speed of sound is 343 m/s, find the diffraction angle u for a 2.0-kHz tone.
(b) What speaker diameter D should be used to generate a 6.0-kHz tone whose diffraction angle is as wide as that for the 2.0-kHz tone in part (a)?