Using the definitions of the normal plane and rectifying plane in Exercises 20 and 21, respectively, find the equations of these planes at the specified points for the vector functions in Exer- cises 40-42. Note: These are the same functions as in Exer- cises 35, 37, and 39. 40. r(1) = (t, +2 , 2+3) att = 1 41/ r(t) = (et, ert, V2t ) at t = 0 42. r(t) = (sin 2t, cos 2t, t) at t =