In the blending model suppose there is a chemical ingredient called C1 that both gasoline and heating oil need. At least 3% of every barrel of gasoline must be C1, and at least 5% of every barrel of heating oil must be C1. Suppose that 4% of all crude oil 1 is C1 and 6% of all crude oil 2 is C1. Modify the model to incorporate the constraints on C1, and then optimize. Don't forget to clear denominators.