Choose the letter that corresponds to your answer. If your answer is not amongthe choices, choose E.

43. Determine the length of the radius of the sphere with equation x2 + y? + 22 -4x - 6y + 2z -1 = 0 (A) 15 (B) 14 (C) V15 (D) V14 44. Determine the equation of the trace of the surface y = x2 + 422 on the xz-plane. (A) 0= x2 +422 (C) y = x2 (B) y = 4z2 (D) y = 12 + 422 45. Which of the following is the equation of the surface of revolution generated by revolving the parabola r = y' in the ry-plane about the r-axis (A) x2+2 + 22 = 0 (C) y? + 22 = 12 (B) x2 + y? = 22 (D) 2 + 22 = 1 46. The following equations are elliptic paraboloid except (A) x2 +y? = z (C) 2 + 22 = 1 (B) x2 + 22 = y (D) x2 + y? = 22 22 47. The graph of the quadric surface with equation 4 9 = 1 is a/an (A) sphere (C) prolate spheroid (B) oblate spheroid (D) paraboloid 48. The graph of the quadric surface with equation x2 - y? + 22 = 0 is a/an (A) elliptic paraboloid (C) hyperboloid of one sheet (B) cone (D) hyperboloid of two sheets 49. The graph of the quadric surface with equation x2 - y2 - 22 = 0 is a/an (A) elliptic paraboloid (C) hyperboloid of one sheet (B) cone (D) hyperboloid of two sheets 50. The graph of the quadric surface with equation x2 + y? + 22 - 2 = 0 is a/an (A) elliptic paraboloid (C) hyperboloid of one sheet (B) cone (D) hyperboloid of two sheets