SAT Question 1180401d: Ratios Rates Proportional Relationships And Units answer and explanation with Desmos solution

Choice B is correct. The land area of the coastal city can be found by subtracting the area of the water from the total area of the coastal city; that is, $92.1-11.3=80.8$ square miles. The population density is the population divided by the land area, or $\frac{621,000}{80.8}=7,686$, which is closest to $7,690$ people per square mile.