Answer:
Virus.
Explanation:
Viruses can't reproduce without invading the cell of another living being.
Answer:
The main dangers worldwide are population growth and resource consumption, climate change and global warming, habitat conversion and urbanisation, invasive alien species, over-exploitation of natural resources and environmental degradation.
Explanation:
<span>"Genetic drift is more likely to have an impact on small populations."
Genetic drift is changing the frequency in the allelic pool of a population. This phenomenon impacts mainly smaller populations because these populations have only a few copies of the alleles present. If a change in the frequency of the alleles happens then it may cause the disappearance of certain alleles because there are only so many copies.</span>
Answer:
2.5 mg
Explanation:
<em>The half-life of a substance is the time required for one half of the substance to decay. In order words, it is the time it will take for a substance to decay into half of its initial size.</em>
For a 20 mg element with a half-life of 30 which decays over a period of 90 years;
The first 30 years, 10 mg would have decayed, remaining 10 mg
The second 30 years, the remaining 10 mg would have decayed to 5 mg
The third 30 years, 5mg would have decayed to 2.5 mg.
Hence, in 90 years, 20 mg of the element would <u>remain only 2.5 mg.</u>