Galactic is referring to the galaxy and cosmos! :)
It can be either they can have a negative or positive charge more specifically negatively charged molecule would called an anion and a positive one would be cation.
"windweathered" because the use of wind weathering would bring the sand all around and it would be wind weathered
Answer:
The weights of all elements are always compared to the Carbon-12.
Explanation:
The weights of all elements are always compared to the Carbon-12 because the mass of carbon is 12 which is the exactly the sum of protons and neutrons.
Oxygen was also considered the standard for some time but later this stander was rejected because in natural O¹⁷ and O¹⁸ were also present and this create the two different atomic mass tables.
AMU:
Atomic mass unit is define as the 1/12 the mass of an atom of carbon-12.
C12 has six neutron and six protons in the nucleus.
This unit is used to express the masses of atoms. We know that masses of atoms are very small and we do not have any such type of balance that can measure very small quantity. So that is way we use this scale to measure small quantity. For example, according to this scale
relative atomic mass of hydrogen is 1.008 amu
relative atomic mass of oxygen is 15.999 amu
relative atomic mass of uranium is 238.0289 amu
relative atomic mass of chlorine is 35.453 amu
Answer: a. solution
Explanation:
A solution is a mixture which contains two or more than two types of components and they can be separated by physical means as well.Example: salt water
Molecule of an element is defined as the aggregate of atoms of similar elements. Example:
. Molecule of a compound is the aggregate of atoms of different elements in a fixed ratio by mass. Example: 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: 
A pure substance is a substance which contains definite composition of only one type of component. Hence, it cannot be separated by physical means. Example: Helium, water