Let P: SCU {o} be the stereographic projection introduced in our course. If y: [a, b] C is a continuously differentiable simple curve, that is, 7 is injective, then answer the followings: (a) Find the formula for the length of the curve ([a, b]) C C. Give the reason for your answer clearly. Hint: Use the notion of the chordal distance d(z, z)= 2|z-z' /1+ |2|1 +22 Note that we can identify C with R =R x R in the above.