2) (-7лу10)2;

2) $$(-7x^9y^{10})^2 = (-7)^2 \cdot (x^9)^2 \cdot (y^{10})^2 = 49x^{9 \cdot 2}y^{10 \cdot 2} = 49x^{18}y^{20}$$

Ответ: $$49x^{18}y^{20}$$