1. The third option is the least soluble in water because it is the chain with the most number of hydrocarbons. Next is the second option while the first one is the most soluble.
2. Statements 1 and 2 are true. The third option is not true all the time because it depends on the structure of the compound.
The difference between the two is that the values in discontinuous variation are fixed, while the values in continuous variation can be changed. :)
Moseley established a more accurate periodic table by closer determination of atomic numbers. Through the results of his measurements of the wavelengths of the X-ray spectral lines of a number of elements which showed that the ordering of the elements by atomic number.