In winter, although many parts of europe have heavy snow falls, the sea ports remain ice-free and ships come and go. what could be a reason why the sea ports remain ice-free? a) a warm ocean current flows along the coast b) a cold ocean current flows along the coast c) the coastal regions have very moderate winters d) warm winds blow from the continent, melting the ice

The answer is (A. A warm current flows along the coast.) Currents carry cold and warm water from place to place. It's an amazing phenomenon that scientists are still trying to fully figure out.  Some think it's caused by wind, others think it's caused by the shifting of the tectonic plates, but one thing's for sure, currents are VITAL for this planets life.

Option (A)

Explanation:

Westerlies are the warm wind blowing in the mid-latitudes from the western direction towards the eastern direction in both the hemisphere. It originates at the 30° latitudes from the high-pressure region and moves towards the region that are located at 60° latitude.

Since Europe is located between the latitude of 30° to 60° in the northern hemisphere, so it experiences the strong westerly winds. As this warm wind comes from the tropical region so they bring warmer air currents often accompanied by rainfall. This wind when reaches the western coastal part of Europa the ice present there gets melted.

so the ports remain ice-free during the winter season.

Thus, the correct answer is option (A).

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.