Answer:
3.9 billion years
Explanation:
The half-life of potassium-40 is the time it takes for half of it to decay.
After one half-life, half of the original amount will remain.
After a second half-life, half of that amount will remain, and so on.
We can construct a table as follows:
We see that the mass will drop to 10 g after three half-lives.
1 half-life = 1.3 billion years
3 half-lives = 3.9 billion years
Ionic bonding
(a brainliest would be appreciated)
Answer:
Glucose is the substance produced during photosynthesis which provides food for plants and animals in a food web.
Explanation:
The main source of energy in a food chain or food web is made by the producers. These producers are mostly plants that make food by the process of photosynthesis. As a result of photosynthesis, glucose is made as the main product whereas oxygen is made as the by-product. Glucose made is used to drive energy for all the activities of the cell. This energy, released from glucose, is carried within an ecosystem from one organism to another.
1.true
2.true
3.fasle
4.true
5.false
6.true
It is false that living organisms contain unique chemical elements which are not found in non-living systems.