Помогите решить 8-10 задание

================== 8 ==================

$lg 8 + lg 5 + lg 2.5 = lg (8 \cdot 5 \cdot 2.5) = lg 100 = lg 10^2 = 2$

================== 9 ==================

$log_29 - log_25 + log_{0.5} 1.8=log_2 \frac{9}{5} + log_{\frac{1}{2} } 1 \frac{8}{10} =\\ =log_2 \frac{9}{5} - log_2 \frac{9}{5} =log_2 (\frac{9}{5}:\frac{9}{5}) =\\ =log_2 1 = 0$

================== 10 ==================
$\frac{log_2 125}{log_20.2}=log_{0.2}125 = -log_55^3=-3$