1 Health benefits of watermelon are actually expansive and the fruit also contains traces of the mineral potassium which helps in the day to day functioning of the body.  The phytochemicals help in lowering blood pressure and the lycopene helps fight cancer and increase immunity.
census - a periodic count of the population. nose count, nosecount. counting, enumeration, numeration, count, reckoning, tally - the act of counting; reciting numbers in ascending order; the counting continued for several hours.
Survey is actually a technique that takes out a sample from a population scientifically to arrive at a decision for the entire population. This article attempts to clarify differences between census and survey to have a better understanding of these two sampling techniques. Census.