Final answer:
The pressure at 30 feet below the surface is the sum of atmospheric pressure and the pressure due to water above, which amounts to approximately 28.06 psi. This calculation utilizes the fact that for every 33 feet of seawater depth, the pressure increases by about 14.7 psi, starting from atmospheric pressure at sea level. However, the given answer options do not match this calculated value, indicating a potential error in the question or answer choices.
Step-by-step explanation:
To determine the pressure at 30 feet below the surface, we can use the knowledge that water exerts a pressure due to its weight, and this pressure increases with depth. The pressure one feels under water is a combination of atmospheric pressure and the pressure exerted by the water above. At sea level, atmospheric pressure is about 14.7 pounds per square inch (psi). For every 33 feet of depth in seawater, the pressure increases by about another 14.7 psi, which is due to the weight of the water above.
Calculating this, the pressure at 30 feet would be:
Pressure at depth = Atmospheric pressure + Pressure due to water
P = 14.7 psi + (30/33 feet * 14.7 psi/33 feet)
P = 14.7 psi + (0.909 * 14.7 psi)
P = 14.7 psi + 13.36 psi
P = 28.06 psi
However, since none of the provided answers (A, B, C, D) are close to 28.06 psi, it seems there may be a misunderstanding or typo in the question or the options provided. It is crucial to verify the question details and the units discussed (feet of water versus depth in seawater) to ensure an accurate response.