Which of the following are not mixtures: milk, tin, sulfur, cough linctus, brass, gold?

Can someone me with these questions plz.

Calculate the molarity of each of the following solutions. part a) 0.12 mol of lino3 in 5.5 l of solution part b) 60.7 g c2h6o in 2.48 l of solution part c) 14.2 mg ki in 100 ml of solution

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