[填空题]
A particular organ pidyh;* xacf05xpe+tm1 tfaly 7i. can resonate at 264 Hz, 440 Hz, and 616 Hz, but not at any other frequena.tiytl1 7 fm+cies in between. (a) Show why this is an open or a closed pipe. (b) What is the fundamental frequency of this pipe? Hz