Answer A is incorrect
A crest is just one point. It is not the distance between 2 crests.
B is incorrect
A trough is just 1 point. It is not the distance between 2 troughs.
C is incorrect.
the amplitude measures the height of a crest from the middle of the wave to the crest (or trough).
D is the correct answer. That is the distance between 2 crests or 2 troughs
Raditionally mangrove forests<span> were viewed as </span>wastelands and unhealthy environments<span>. People therefore reasoned that </span>their<span> removal would improve the health ...</span>
<span>According to its definition, friction is generated when atoms interfere with each other on sliding surfaces.</span>
W = F x D
The work you put into a machine -- the input force -- is the force you apply times the distance you apply it. The work done by the machine equals the resisting weight times the distance it moves when you perform the work.