In the process of fractional distillation, the components of petroleum are separated according to
a. boiling point
b. carbon-to-hydrogen ratio
c. reactivity with oxygen
d. melting point

It is A because fractal distillation is the separation of components in mixtures according to their boiling points.

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.