1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
natulia [17]
2 years ago
14

Select the elements that have 4 valence electrons.

Biology
1 answer:
Free_Kalibri [48]2 years ago
7 0
Carbon has 4 valence electrons
You might be interested in
One of your authors was once involved in a research study where a newly developed pain drug was being tested. all participants c
loris [4]

The primary ethical guidelines that apply to this experiment are those of human experimentation.

The use of humans as subjects of experimentation would seem to demean their human dignity. The issue of abuse of the human subjects and also the prospects of the clinical trial going wrong (such as causing an adverse effect on the subjects) also raise ethical challenges even when the subjects are volunteers.  In case of a clinical error, what is the right compensation?


8 0
3 years ago
Read 2 more answers
Amino acid is to protein as
Len [333]
A, the amino acid of a lipid is a fatty acid.
3 0
3 years ago
Read 2 more answers
-. In which phylum does a coelom first appear?
adoni [48]

Answer:

The answer is a. Annelida

8 0
3 years ago
PLEASE HELP?!! WILL MARK BRAINLY
saw5 [17]

Answer:

You just posted his one? Credit to: Vermont Legislative Research Shop

Explanation:

If you need extra resources: Lawn and garden chemicals, such as fertilizers enter the groundwater in two ways. In the first method, the chemicals can enter the groundwater by rainwater into a stream as runoff. This is especially problematic in urban environments where hard-surfaced roads allow rainwater to move over them without benefit of soil acting as a filter (Rosen and White, 1999). The water in streams replenishes groundwater, so the chemicals are absorbed into the groundwater as well. The second method of contamination is through leaching, which is the downward movement of a substance through the soil. The fertilizer may also dissolve into the surface water, which recharges the groundwater (Virginia Cooperative Extension, 1996).  Nitrate is highly soluble and readily leaches into groundwater. Water with over 10 parts per million nitrate-nitrogen can cause methemoglobinemia, an inability to use oxygen in infants. The nutrient phosphorus harms clear, free water by creating algal blooms. This process, known as eutrophication, turns the water green, clouds the water, causes odor problems, and depletes the oxygen for fish and other species, effectively suffocating them (Lake Champlain Basin, 1998).  To ensure that the groundwater does not get so contaminated as to be unhealthy, in 1986 the Department of Food and Markets implemented the Pesticide Monitoring Program. The goal of this program is to test wells in agricultural areas to help farmers learn about practices that prevent pesticides from leaching into the groundwater, and to conserve the nutrients in fertilizers and manure in the soil. This program is funded by fees taken from companies that sell pesticides and fertilizers in Vermont (Vermont Department of Agriculture, Food and Markets, 1998).

7 0
3 years ago
How much energy is passed on from each level
Anuta_ua [19.1K]

Answer:

The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat

8 0
3 years ago
Other questions:
  • Celiac disease causes the destruction of the villi cells. Which of the following is most likely to happen to people with celiac
    15·1 answer
  • What is the difference between a skilled hacker and an unskilled hacker (other than the
    8·1 answer
  • What is the term for the junction between one nerve cell and the next called?
    5·1 answer
  • A fire in the Everglades damages a large area. A forest fire in Alaska of the same size experiences similar damages. Which ecosy
    6·2 answers
  • How does wind primarily cause erosion
    6·1 answer
  • MAX POINTS!
    12·2 answers
  • What is the difference between endocrine and exocrine glands?
    14·1 answer
  • A team of researchers calculates that a glacier will melt completely away in the next 100 years. Which land structure will most
    7·1 answer
  • In the marine food web, which organism are considered predators to more than one organism?
    12·2 answers
  • When encountering a powerboat in darkness or reduced visibility, what do visible white and red lights indicate?.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!