The right answer to this question is A. a crest that is toppling over. When a surfer rides an ocean wave on her surfboard, she is actually riding on a crest. The crest is the point on a wave with the maximum value or upward displacement within a cycle.
Complete question:
Find the pressure exerted by a waterbed with dimensions of 2 m x 2 m which is 30 cm thick. (hint: use 1000 kg/m³ as density of water)
Answer:
The pressure exerted by the waterbed is 2940 N/m²
Explanation:
Given;
Length of waterbed, L = 2 m
Width of waterbed, W = 2 m
Height of waterbed, H = 30 cm = 0.3 m
density of water, ρ = 1000 kg/m³
Hydrostatic pressure derivation:

The hydrostatic pressure exerted by the waterbed is directly proportional to the height of the waterbed. Thus, the hydrostatic pressure increases with increase in height of the waterbed.
Hydrostatic Pressure exerted by the waterbed:
P = ρgH
P = 1000 x 9.8 x 0.3
P = 2940 N/m²
Therefore, the pressure exerted by the waterbed is 2940 N/m²
Answer:
B. The number of wave cycles that pass through a specific point within a given time period.
The bending occurs because light travels more slowly in a denser medium.