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.
Biogeographic isolation means that a population is separated and there are two populations in two different areas. As normal mutations take place, but certain mutations will be seen as advantageous in the different areas. For. Example if an area had taller trees the organism may develop a gene to grow taller. This is then passed down to offspring. This process continues so that more gene differences are created within the species and the frequency of these alleles increased: leading to two different species developing-
Answer: Zacharias Janssen is credited with inventing the microscope.
Explanation:
ANSWER: Biological biodiversity refers to all the different kinds of life that are obtainable in a particular ecosystem, this include all the plants and animal populations that are found in a particular geographical area.
Biodiversity supports healthy ecosystem because it enhances the productivity and the survival of the ecosystem. For instance, in a situation where there are large number of different plant population in an ecosystem, such population will present variability in genetic make up. If a negative event occur in the ecosystem, it will be possible for some plants to survive. But, in a situation where it is only one type of plant that is obtainable in the ecosystem, it will be quite easy to wipe all of them out at once. For instance, a disease outbreak can easily destroy all the plants.
