Answer: It was obtained 8515 years ago
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) to find the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.


b) for completion of 36% of reaction


t = 8515 years
The time was 8515 years.
Clouds form when moist, warm rising air cools and expands in the atmosphere. The water vapor in the air condenses to form tiny water droplets which are the basis of clouds.
The statement 'symbiosis is a relationship between organisms in which both benefit' is TRUE about this they of ecological interaction.
<h3>What is symbiosis?</h3>
Symbiosis is a particular class of ecological interaction in which both organisms are favored by this they of relationship.
Symbiosis examples include for example the association that involves clownfish and an anemone, which are both benefited by their interaction.
In conclusion, the statement 'symbiosis is a relationship between organisms in which both benefit' is TRUE about this they of ecological interaction.
Learn more about symbiosis here:
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