Read the following excerpt from h. g. wells' the war of the worlds, and answer the question that follows:

the planet mars, i scarcely need remind the reader, revolves about the sun at a mean distance of 140,000,000 miles, and the light and heat it receives from the sun is barely half of that received by this world. it must be, if the nebular hypothesis has any truth, older than our world; and long before this earth ceased to be molten, life upon its surface must have begun its course. the fact that it is scarcely one seventh of the volume of the earth must have accelerated its cooling to the temperature at which life could begin. it has air and water and all that is necessary for the support of animated existence.

which of the following details comes from supporting evidence?
it is not necessary to remind the reader.
mars is a planet.
the writer has done research.
mars is older than earth.