DSE 2020 Question 27: General equilibrium and exchange economies

An exchange economy has goods $x,y$ and agents $1,2$ with endowments $(\omega^1_x,\omega^1_y)=(0,9)$ and $(\omega^2_x,\omega^2_y)=(10,0)$, and utilities $u_1(x,y)=\min\{x,y\}$ and $u_2(x,y)=\min\{x,y\}$. The competitive equilibrium price ratio $p_x/p_y$ is