The Florida Keys are an archipelago (chain of islands) off the southern coast of Florida. The Keys are made of mainly softer materials like limestone and fossilized coral. The Hawaiian Islands are also an archipelago, but are made of much harder igneous rock. Which of the following explains why the Hawaiian Islands are made of such different materials than the Florida Keys? A.
Coral does not grow near the Hawaiian Islands.

B.
The Hawaiian Islands were built mostly by people.

C.
Igneous rocks are only found in the Hawaiian Islands.

D.
The Hawaiian Islands formed through volcanic eruptions.

the answer is a) a shiprock was formed by igneous process

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.