Answer:
five half lives
Explanation:
Half-life is the time required for a quantity to reduce to half of its initial value.
How many half lives it would take to reach 3.13% form 100% of it's initial concentration:
100% - 50% : First Half life
50% - 25%: Second Half life
25% - 12.5%: Third Half life
12.5% - 6.25%: Fourth Half life
6.25% - 3.125%: Fifth Half life
This means it would take five half lives to get to 3.125% (≈ 3.13%) of it's original concentration.
It is true that at any given location, the physical properties of a substance do not change.
Answer:
when population increases the amount of carbon dioxide also increases as population use oxygen and release carbon dioxide
Coal is being formed from decayed fossils and remains. These materials are smashed, "compacted" together until their chemicals merge together from the pressure of the compacting this is also how diamonds form from coal just more heat and more pressure. This process is called compaction. Without such, no coal will be present.