Imagine that the cruise liner on which you have been having the holiday of a lifetime has just sunk, following a devastating explosion in her boilers. with very little time available to save yourself,you now find you are adrift in a lifeboat with other survivors, miles from the nearest land without the means of contacting the outside world to summom help. your lifeboat is totally alone and contains other survivors like yourself. the lifeboat,however,is not quite full and has the capacity to take four more survivors and no more. as time goes by, the lifeboat comes across the following survivors in the water: