/kloc-Euler, a Swiss mathematician in the 0/8th century, proved an interesting relationship between the number of vertices (v), the number of faces (f) and the number of edges (e) of a simple polyhedron, which is called Euler formula. Please observe the following simple polyhedral model and answer the following questions:

(1) according to the above polyhedron model, complete the blanks in the table: number of polyhedron vertices (v) number of faces (f) number of edges (e) tetrahedron 4 4 6 6 cuboid 8 6 12 octahedron 6812 dodecahedron 20 12 30. Find the number of vertices (v

(2) If the number of faces of a polyhedron is 8 larger than the number of vertices and has 30 sides, then the number of faces of this polyhedron is 20 20.

(3) The shape of the glass vase is a simple polyhedron, and its outer surface consists of two polygons: triangle and octagon. It has 24 vertices, and each vertex has 3 sides. Let the number of triangles and octagons on the polyhedron be x and y, respectively, and find the value of x+y.