Answer:
The answer is c.
Explanation:
Age structure data can include all of these aspects except for c I believe.
The central nervous system (CNS), which is made up of the brain and the spinal cord, and the peripheral nervous system (PNS), which is comprised of nerves and ganglia (small concentrations of grey matter).
The brain sends messages to the peripheral nerves in the body via the spinal cord, these have control of muscles and internal organs.
Answer: The correct answer is black because the product of its side and mass is lower.
Explanation: Density of a substance is defined as the mount of matter that can be stored in a given volume.
Mathematically,

As, density is inversely proportional to the volume of the substance.
The substance will be more denser if it has less volume and it will be less denser if the volume is more.
We are given two cubes having different sides.
Volume of the cube is calculated by using the formula:

where, a = side of the cube.
Black: The side of this cube is 2 and volume will be =
Yellow: The side of this cube is 3 and volume will be =
As, the volume of black cube is less. So, this cube will be more denser.
Density of black cube: 
Density of Yellow Cube: 
Hence, black cube will be more denser because the product of its side and mass is lower.
Answer:
Youngest to Oldest
Shale with ammonite
Limestone with unknown fossil
Basalt
Sandstone with trilobite
Answer: D. The kinds of organisms that lived there long ago.
Explanation: Finding fossils in an area can help us learn about the kinds of organisms that lived there long ago. The fossil leave traces behind about what type of animal lived there and who the animal was.