$$0.125^3 \cdot 0.4^3 \cdot 4^3 = 0.125^3 \cdot (0.4 \cdot 4)^3 = 0.125^3 \cdot (1.6)^3 = (0.125 \cdot 1.6)^3 = 0.2^3 = 0.008$$
Ответ: 0.008