3. Let v(t) be a unit speed regular parametrizationonzero curvature. Consider the surface patch a(t, 0) = v(t) + (Rcos0) n(t) + (Rsin0) B(t) where R is a positive constant and n(t) and B(t) are respectively the principal normal and binormal vectors at 7(t). (i) Find conditions on a and k(t) which guarantee that o is a regular surface patch. (ii) Compute the first fundamental form of the surface patch. (iii) Evaluate the area of the part of the surface patch where a