Answer:
4589.05 year
Explanation:
The relation of activity is given by [tex]A=A_0e^{\lambda t}[/tex] we have given [tex]\frac{A}{A_0}=0.574[/tex]
Half life [tex]T=5730\ years[/tex]
We know that half life [tex]T=\frac{0.693}{\lambda }[/tex]
[tex]\lambda =\frac{0.693}{5730}=1.2094\times 10^{-4}\ per\ year[/tex]
So [tex]0.574=e^{-1.2094\times 10^{-4}t}[/tex]
[tex]e^{1.2094\times 10^{-4}t}=\frac{1}{0.574}=1.742[/tex]
[tex]{1.2094\times 10^{-4}t}=ln1.742=0.555[/tex]
[tex]t=\frac{0.555}{1.2094\times 10_{-4}}=4589.05\ year[/tex]