7. log₅0.2 + log₀.₅4

log₅0.2 = log₅\(\frac{1}{5}\) = log₅(5⁻¹) = -1.
log₀.₅4 = log(1/2) 4 = log(2⁻¹) 2² = -2 log₂2 = -2. Следовательно, log₅0.2 + log₀.₅4 = -1 + (-2) = -3.
Ответ: -3