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\begin{array}{ll}150=130 e^{k 10}+35 & \text { Substitute }(10,150) \\115=130 e^{k 10} & \text { Subtract } 35 . \\\frac{115}{130}=e^{10 k} & \text { Divide by } 130 . \\\ln \left(\frac{115}{130}\right)=10 k & \text { Take the natural log of both sides. } \\k=\frac{\ln \left(\frac{115}{100}\right)}{10} \approx-0.0123 & \text { Divide by the coefficient of } k .\end{array}