Answer:
The answer is A
Explanation:
You can tell that rocks are older or younger depending on if other layers overlap. B is the oldest because all the others cover it, C is the second youngest because D and A overlap it. From what I could tell, when I took the test, it was either A or D, neither overlap each other so I was not sure so I guessed A and got it right. Though it could be looked at that A is smaller than D since its still growing and building.
Since mitosis is the division of cells, in this case, skin cells, it allows the dead skin cells to fall off. Also, mitosis can fix any injuries. Without mitosis, these things would not happen.
B.) Marshmallows catching fire.
Three factors that determine the reactivity of elements are the
valence electrons are the electrons in the outermost electron shell of an atom.
The number of electrons in an atom's outermost valence shell governs its
bonding behaviour. That is why in periodic table the elements were put together
according to their numbers of valence electrons.
METALS
The most reactive kind of metallic element is a metal from
Group 1 sodium or potassium.
An atom in Group 1 has only one valence electron.
NON-METALS
A nonmetal tends to attract another valence electrons to
attain a full valence shell.