Earth is comprised of four systems, or spheres. which of these spheres do each of the five branches of earth science study?

The four systems of Earths spheres are: 
1)Lithosphere : it comprises all the rock, stones and suck like.
2)Hydrosphere : comprises with the liquid.
3)Biosphere: comprises things we do with the livings.
4)Atmosphere: Air and its compositions.

Geology

Explanation:

Geology is the study of Earth and every sphere has something to do with Earth.

K is bigger in atomic size. The metallic character increases as the size increases.

Explanation:

Reactivity of a metal is defined as the tendency of an element to lose electrons. The metallic character increases as we move down a group and it decreases as we move across a period.

When the size of an element increases, the valence electrons gets away from the nucleus and the tendency of an element to loose electrons increases.

In a group, the size of an element increases because there is an addition of new shell and electron is added in that shell.

Thus for alkali metals, the metallic character increases from Lithium to sodium to potassium and so on.