Answer
(a) $-\frac{2}{3}$
(b) $4$
(c) $-1$
Work Step by Step
Quick overview of Logarithms: $\log_x{a}=b$, where $a=x^b$
$\log_x{x^b}=b$
$\log_x{a}-\log_x{b}=\log_x{\frac{a}{b}}$
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(a) $\log_8{0.25}=\log_8{\frac{1}{4}}=\log_8{1}-\log_8{4}= 0-\log_8{8^{\frac{2}{3}}} = -\frac{2}{3}$
(b) $\ln e^4 = 4$
(c) $\ln{\frac{1}{e}}= \ln e^{-1}=-1$
