The waves are not noticeable out at sea because of their long wavelength.
这些海浪在海上看起来不是很明显，因为它们的波长很长。
2
What is the meaning of "the length of a wave" according to paragraph 3?
根据第三段，“the length of a wave” 是什么意思？
3
The entire length of the tower is equipped with a feeder (a coaxial wave-guide) through which signals are transmitted from the transmitter to the antenna on the spire.