Answer:
[tex]\large\boxed{y^{60}}[/tex]
Step-by-step explanation:
[tex](y^{-5})^{-10}y^{10}\qquad\text{use}\ (a^n)^m=a^{nm}\\\\=y^{(-5)(-10)}y^{10}=y^{50}y^{10}\qquad\text{use}\ a^n\cdot a^m=a^{n+m}\\\\=y^{50+10}=y^{60}[/tex]
