A player in a videogame is currently placed at the point P= (1,-2,.5). One of the (many) triangles which make up the objects in the game has vertices at R= (1.9,8.1,12.2), S= (2.1,8.2,12.1) and T = (1.95, 8.1, 12.25). Suppose the player can currently see the "outside" face of the triangle. Find the outward facing normal vector n to the triangle as well as the angle between n and the displacement vector PR. What is the angle formed by the player's line of vision and the face of the triangle?

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