1- A farmer plans to mix two types of food to make a mix of low-cost feed for the animals in his farm. A bag of food A costs $10 and contains 40 units of proteins and 20 units of minerals. A bag of food B costs $12 and contains 30 units of proteins and 20 units of minerals. How many bags of food A and B should the consumed by the animals each day to meet the minimum daily requirements of 150 units of proteins and 90 units of minerals at a minimum cost