Answer:

Explanation:
The formula for density is ρ
(where
represents mass, and
represents volume).
With this formula, we can calculate the density of the object:
ρ 
Hope this helps :)
Answer:
4) molecule, cell, organ system, population, ecosystem, biosphere
Explanation:
Various biomolecules such as carbohydrates, proteins, lipids, etc. together make the cells. Cells are the structural and functional units of life. A group of cells destined to perform specific functions makes tissues and various specific tissues together make an organ.
An organized group of tissues and organs that work cooperatively to perform a specialized set of functions is called an organ system. For example, the digestive system includes organs involved in the breakdown of nutrients.
A group of organisms of the same species that live in a defined geographic area at the same time make a population. Ecosystem refers to an interacting system including a biotic community and its nonliving, physical environment. The biosphere includes all of the parts of Earth where life forms exist and include the atmosphere, the hydrosphere and the lithosphere.
Answer:
People, fossils fuels,land,living things
Explanation:
Answer:
<em>The correct option is d) once the electrical impulse reaches a certain level of intensity (its threshold), it fires and moves all the way down the axon without losing any intensity.</em>
Explanation:
In the field of biology, the all-or-nothing law can be described as a principle which focuses on the strength with which a nerve or muscle fibre responds to a particular stimulus, this strength being independent of the strength of the stimulus. The functioning of the impulse is just like the trigger of a gun. The more the force of a stimulus, the more will be the intensity of the nerve impulse.
Peces, algunos anfibios, moluscos, artrópodos, gusanos