Now what about the frequency of the second harmonic -- the standing wave with 3 nodes and 2 antinodes?

那么二次谐波的频率呢... 具有 3 个节点和两个偏移中心的驻波？

And just like a string with two fixed ends, the second harmonic for a pipe with two open ends also covers a full wavelength.

两端固定的和弦，覆盖泛音 第二种是全波长的双端长笛。