What would happen to temperatures on earth if the sun’s heat was not distributed throughout the atmosphere?

You would litterally be able to fry an egg on a sidewalk. The sun would SCORCH the Earth Killing everything, even humans.

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.