Consider a two-person, two-commodity, pure-exchange, competitive economy. The consumers' utility functions are U₁ = q₁₁q₁₂ + 12q₁₁ + 3q₁₂ and U₂ = q₂₁q₂₂ + 8q₂₁ + 9q₂₂ respectively (where q_ij denotes the consumption of commodity Q_j by consumer i, with i = 1, 2 and j = 1, 2). Consumer 1 has initial endowments of 8 and 30 units of Q₁ and Q₂ respectively; consumer 2 has 10 units of each commodity. 

Determine the excess demand function for the two consumers. Detennine an equilibrium price ratio for this economy. (300 words) (25 Marks)