Answer: half life
Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:

t= time required
k= disintegration constant
x= amount of substance left after time t
a= initial amount of substance
when one half of the sample is decayed, one half of the sample remains and t can be represented as 
at
, 


<u>The addtion of energy</u> <span>is usually needed to help a decomposition reaction occur</span>
Polyester and polyamide would be two synthetic polymers, created by condensation reaction.
Answer:
3 hours
Explanation:
To know the the correct answer to the question given above, it is important we know the definition of half-life.
The half-life of a substance is simply defined as the time taken for half the substance to decay.
Considering the diagram given above, the initial mass of the substance is 100 g.
Half of the initial mass = 100 / 2 = 50 g
Now, we shall determine the time from the graph taken to get to 50 g.
Considering the diagram given above, the time taken to get to 50 g is 3 hours.
Therefore, the half-life of the material is 3 hours.