Hello, here’s the answer to your question. Converting ammonia to nitrate, which is absorbed by plants
It doesn't?
Heat transfers from hot objects to cold objects and for ice to melt it has to increase the temperature.
It changes precipitation patterns, causes strong storms, and transfers warm and cold air.
Half-life is the time taken for the concentration of the substance to reduce by 50%. The original sample of strontium had a mass of 1.6 gms. Thus, option d is correct.
<h3>What is half-life?</h3>
The half-life of any radioactive substance is the time period at which the concentration will get reduced to half the initial amount. The initial mass of Sr-90 is calculated as,

Given,
Quantity of the remaining substance N (t) = 0.40 gm
Initial radioactive substance quantity
=?
Time duration (t) = 56 years
Half-life = 28 years
Substituting values above:

= 1.6 gm
Therefore, option d. the initial mass of Sr is 1.6 gm.
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Answer:
the person above me is very right
Explanation: