Concept:Use the angle-sum property of triangles and the alternate interior angles formed by parallel lines.Explanation:In △NOP, the angles at N and O are 129∘ and 37∘.Thus,∠NPO=180∘−(129∘+37∘)=14∘.Since MN∥PO and PN is a transversal, alternate interior angles are equal.So,∠MNP=∠NPO=14∘.Now in △MNP, we have ∠PMN=112∘ and ∠MNP=14∘.Using the angle-sum property of a triangle,y=∠MPN=180∘−(112∘+14∘)=54∘.