Explain the circumstances in which the scene opens and the reaction of different people aboard

Sailors try to keep a ship ‹from running aground on the rocks in a stormy sea. The passengers ‹are Alonso, the King of Naples, Alonso's son Ferdinand, Alonso's brother Sebastian, Alonso's advisor Gonzalo, and Antonio. The boatswain says that even kings cannot "command these elements" of wind and water, and tells Antonio and Sebastian that they can either "keep below" or help the sailors. The noblemen take offense at being ordered around by a mere sailor, and both show a mean-tempered streak in this encounter.