The entries in the first table are as follows. Unit profit. Activity 1: $20. Activity 2: $40. Activity 3: $30. The entries in the second table are as follows. Resource 1. Resource used per unit produced, activity 1: 3. Resource used per unit produced, activity 2: 5. Resource used per unit produced, activity 3: 4. Totals: 400 <= available, 400. Resource 2. Resource used per unit produced, activity 1: 1. Resource used per unit produced, activity 2: 1. Resource used per unit produced, activity 3: 1. Totals: 100 <= available, 100. Resource 3. Resource used per unit produced, activity 1: 1. Resource used per unit produced, activity 2: 3. Resource used per unit produced, activity 3: 2. Totals: 200 <= available, 200. The entries in the third table are as follows. Units produced. Activity 1: 50. Activity 2: 50. Activity 3: 0. Total cost: $3.00. Where are the changing cells located