Question 848888
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Hi,
E(x) = E[0]e^(-x/x0)
E(x0) = E[0]e^(-x0/x0)
E(x0) = E[0]e^(-1)

loses 91% of its initial energy ( 9% remains)
E(x) = E[0]e^(-x/x0)
E(x)\E[0] =e^(-x/x0)
.09 =e^(-x/x0)
ln(.09)= -x/x0
(-x0)ln(.09) = x