* 1. 1 point Equation of the Right Cireular Cone when vertex is the Origin, axis is zaxis and Sem-vertical angle is a then (a) x- = z tan-a (C)x+ y = z tan-a (b) x = zcota (d)x-y = z* sin"a Oa Ob O C O d 19, * 1 point The section of sphere cut by the plane through the center of sphere is (a) Circle (C) Parabola Sphere (b) (d) Great Circle