Suppose a boat needs to travel in water with a depth of at least 3 meters. Given the two-dimensional ocean depth map shown below, which of the following would be the safest path for the boat to travel, west-to-east, across this ocean? straight across at 30.4° N latitude straight across at 30.3° N latitude straight across at 29.5° N latitude diagonally from the top left corner (30.4° N, 90.4° W) to the lower right corner (29.5° N, 89.5° W)

Correct Answer: B. straight across at 30.3° N latitude

Explanation: The path that is straight across at 30.3° N is the only path, out of the given options, along which the ocean depth is always 3 meters or even more. Oberve that, along the path at 30.4° N, there is one location (30.4° N, 90.1° W) at which the ocean depthis 2 m. Also along the path at 29.5° N, the entire path has an ocean depth of 1 m. The diagonal path would take the boat through deeper water (depth 3 m through 5 m) near the top left corner and through shallow water (depth 1 m) as it moves closer to the lower right corner.