Answer:
332,193 years
Step-by-step explanation:
From the question above, we are to calculate the time in an half life question, hence, the formula is given as
t = In(Nt/No) ÷ -(In2/t½)
Where
t = time is takes for an substance to decay or reduce
Nt = Amount of sample after time = 2g
No = Initial amount of sample = 20g
t½ = Half life = 100,000 years
Hence,
t = In(2/20) ÷ (In 2/ 100,000)
t = 332192.80948874 years
Approximately = 332,193 years
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