Howdy! can be replied to with just a nod and a smile. It simply means Hi! in Texan - not How are you doing?. Or you might reply, Hey Y'all Doon? if you want to engage in proper Texan interactions. Replying in proper English, well pronounced, with each syllable clearly spoken, is HIGHLY discouraged.
The crest of a wave is the point of maximum positive displacement, or upward movement, away from equilibrium, or an undisturbed state. The opposite of crest is trough, which is the point of the greatest negative, downward displacement.
The height of a wave is called the amplitude. The top of the wave is called the crest. The bottom of the wave is called the trough.The frequency of the wave is the number of wave crests passing a given point in a specific amount of time. Frequency is measured in hertz. Davin Erickson.