The city of Pisa was at the beginning a simple but important Italian seaport. With its growth, so did its religious buildings. Its fame and power grew gradually over the years, as the people of Pisa were involved in various military conflicts and trade agreements.
Tides occur as a response to the gravitational attraction of the Sun and Moon and the rotation of Earth. There are three basic tidal patterns - diurnal, semidiurnal, and mixed. Diurnal tides are characterized by one high and low tide a day.
I think the correct answer from the choices listed above is option A. Lawn fertilizer is the source that is the <span>most difficult to track and regulate. This is because fertilizer used in a lawn are not measured strictly and most likely there are no clear regulations about the use of it. Also, runoff of such is very difficult to follow. It can go anywhere. Hope this answers the question.</span>
