Answer:
Explanation:
We are asked to find how much of a 40 gram sample remains after 12 years.
Iron-55 has a half-life of 3 years. Therefore, after 12 years, 4 half-lives have been completed.
- 12 years/3 years = 4 half-lives
Every time a half-life is completed, half of the sample's mass decays. Remember we start with a 40 gram sample.
- 1 half- life: 40 g / 2 = 20 g
- 2 half-lives: 20 g / 2= 10 g
- 3 half-lives: 10 g / 2 = 5 g
- 4 half-lives: 5 g / 2 = 2.5 g
There is also a formula that can be used to solve this problem.
Where A₀ is the initial amount, t is the time, and hl is the half-life.
We know 40 grams is the inital amount, 12 years is the time, and 3 years is the halflife.
After 12 years, <u>2.5 grams </u> of Iron-55 will remain.
3 is the answer.
Binary fission is a type of asexual reproduction and is the most common method of reproduction in prokaryotes. It may occur in some unicellular (single- celled) eukaryotes..
Eukaryotes use sexual recombination during reproduction to create or generate genetic variation and thus the resulting offspring will have a mixture of the parents' genetic characteristics.
Prokaryotes on the other hand will simply produce clones of themeslves through binary fisson. After the process of replicating its own genetic material, the prokaryote simply divides into two daughter cells that are almost identical in size and that concludes the process.
Answer:
A virus is a tiny infectious biological agent that can only replicate or duplicate inside the host cell. These infectious agents can infect all different types of living organisms ranging from animals and plants to microorganisms and archaea and bacteria.
Virions are ineffective particle or form of the virus outside of the host cell, with RNA or DNA and a protein capsid.
The main role of these infectious agent virions is to transfer the DNA or RNA genome from itself to the cell of host and expressed the gene which means produce proteins from the genome transferred to the host cell.
Answer:
Charles Ehler: incorrect.
Wendell Mullison: correct.
Robert Rodriguez: correct.
Judy Johnson:correct.
Explanation:
-Charles Ehler´s statement is incorrect because in order for a chemical company launch a new product it must pass several tests, that´s why products lasts years in proves, there are several tests such as the environment test that proves that the product doesn´t affect other species, or the human safety that makes sure the product doesn´t affect human health.Wendell Mulison´s statement proves to be correct with this as well.
-Robert Rodriguez´s statement is correct because even though there are several tests that take care human healt there are just a few based on the damage pesticides produce to the land where are used.
-Judy Johnson´s statement is correct because science has proved that the resistant of parasites as being increasing with the products tat are used to combat them. Bacterias are an example of it, many drugs used against bacterias are now useless for some people because of the resistantthey have developed.
-One specie that can be taken as a pesticide can be the ground snail, that affects some plants and also may contain a parasite aclled "Hepatic fasciola" that affects sheeps and goats of farmers.
-One viable method to control pesticides is the sue of other species to control them, this specie has to be adequate to the land, for example, if a farmer wants to get rid of the ground snails because of the parasite and the damage they do to their platings, they can introduce ducks to the farm that eat them without damaging the land with any kind of chemical product.
Answer:
25. red
24. A. Temperature and Luminoscity
Explanation:
