The oceanographers define salinity by the number of grams of salt per kilogram of water.
Salinity is illustrated as how much salt is present in the given amount of water. It is dependent upon how much salt is found in the ocean in the specific regions. If there is a sunny environment, it may evaporate an ample amount of water, and leave behind a lot of salt, thus, the water has more salinity.
The salinity of the ocean is usually measured in Practical Salinity Unit (PSU), it is a unit based on the characteristics of seawater conductivity.
a specific hypothesis to test with a controlled experiment
The sample that has the highest solubility is THE FIRST SAMPLE [TABLE SUGAR NO 1].
Solubility refers to the quantity of a solute that will dissolve in a given volume of solvent at a given temperature and pressure. The question above tells us that equal amounts of sugar and table salts were used. But looking at the table given in the question, you will see that sample 1 has the highest amount of solute that dissolve, that is 80, the rest of the samples have values that are lower than that.