Давай решим каждое выражение по порядку:
1) $$0.5^8 \cdot 2^8 = (0.5 \cdot 2)^8 = 1^8 = 1$$
2) $$2^5 \cdot 5^5 = (2 \cdot 5)^5 = 10^5 = 100000$$
3) $$\left(\frac{1}{3}\right)^6 \cdot 6^6 = \left(\frac{1}{3} \cdot 6\right)^6 = 2^6 = 64$$
4) $$0.125^9 \cdot 8^9 = (0.125 \cdot 8)^9 = 1^9 = 1$$
5) $$\left(1\frac{7}{9}\right)^{11} \cdot \left(\frac{9}{16}\right)^{12} = \left(\frac{16}{9}\right)^{11} \cdot \left(\frac{9}{16}\right)^{12} = \frac{16^{11}}{9^{11}} \cdot \frac{9^{12}}{16^{12}} = \frac{9^{12}}{9^{11}} \cdot \frac{16^{11}}{16^{12}} = 9 \cdot \frac{1}{16} = \frac{9}{16}$$
6) $$0.25^{20} \cdot 4^{18} = \left(\frac{1}{4}\right)^{20} \cdot 4^{18} = \frac{1}{4^{20}} \cdot 4^{18} = \frac{4^{18}}{4^{20}} = \frac{1}{4^2} = \frac{1}{16}$$
Ответы:
1) 1
2) 100000
3) 64
4) 1
5) 9/16
6) 1/16