Identify the following surfaces as an elliptical paraboloid, hyperbolic paraboloid, a hyperboloid of one sheet, a hyperboloid of two sheets, a cone, a circular cylinder, an elliptical cylinder, or a parabolic cylinder, and identify the axis of symmetry as the x-axis, the y-axis, or the z-axis.

a. ? elliptical paraboloid hyperbolic paraboloid hyperboloid of one sheet hyperboloid of two sheets cone circular cylinder elliptical cylinder parabolic cylinder ? along the x-axis along the y-axis along the z-axis -6 x^2 - 9 y^2 + z^2 = 1

b. ? elliptical paraboloid hyperbolic paraboloid hyperboloid of one sheet hyperboloid of two sheets cone circular cylinder elliptical cylinder parabolic cylinder ? along the x-axis along the y-axis along the z-axis 8 y^2 - 5x^2 - 6 z^2 + 1 = 0

c. ? elliptical paraboloid hyperbolic paraboloid hyperboloid of one sheet hyperboloid of two sheets cone circular cylinder elliptical cylinder parabolic cylinder ? along the x-axis along the y-axis along the z-axis 5 x^2 + 5 y^2 - z = 0

d. ? elliptical paraboloid hyperbolic paraboloid hyperboloid of one sheet hyperboloid of two sheets cone circular cylinder elliptical cylinder parabolic cylinder ? along the x-axis along the y-axis along the z-axis -2 x^2 + 8 y^2 - z^2 = 0

e. ? elliptical paraboloid hyperbolic paraboloid hyperboloid of one sheet hyperboloid of two sheets cone circular cylinder elliptical cylinder parabolic cylinder ? along the x-axis along the y-axis along the z-axis