a) b) | c) | ]Find the equations of the normal line to the given surface at the point (,1,-1). Find the equation of the tangent plane to the given surface at the point (,1,-1). | Find two other points on the above surface?

Consider the points P = (3, 2, 1) and Q = (1, 2, 3) in R3. (1) What is the equation of the sphere that is centered at P and touches Q? (2) What is the equation of the plane containing the triangle ∆OPQ (where O is the origin)? (3) What is the equation of the line passing through O that’s parallel to line PQ?

Help me please