4.

(1 pt)
if gravity always pushes down, what prevents a person from sinking down into the ground?

a.
nothing prevents a person from sinking into the ground.

b.
gravity only pushes with enough downward force to let a person touch the ground.

c.
a person's body is pushing up, balancing the downward force from gravity.

d.
the earth is pushing up on a person, balancing the downward force from gravity.

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.

Energy defines the different "states" of matter. in no more than 3 sentences, describe the amount of kinetic energy that each of the 3 states of matter possesses and relate that to the atom/molecular motion of each "state".

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?