Let \( b=\log k \). Write the following expression in terms of \( b \). Assume \( k>0 \). \( \log \left(k^{5}\right)=\square \)

To rewrite the expression in terms of \( b \), we can use the power rule of logarithms, which states that \( \log(a^n) = n \log(a) \). In this case, we apply the rule to the given expression: \[ \log \left(k^{5}\right) = 5 \log(k) \] Since \( b = \log(k) \), we can substitute \( b \) into the equation: \[ \log \left(k^{5}\right) = 5b \] Thus, the expression \( \log \left(k^{5}\right) \) can be written as \( 5b \).