Represent (If Possible)the Following Surfaces as Graphs of Functions F(x $z ^ { 2 } = 4 x ^ { 2 } + 4 y ^ { 2 }$

Essay

Represent (if possible)the following surfaces as graphs of functions f(x, y), and as level surfaces of the form g(x, y, z)= c.(There are many possible answers.)
(a)The upper half of the sphere of radius 3, centered at (5, 5, 0).
(b)The lower half of the cylinder of radius 4 around the x-axis.
(c)The cone $z ^ { 2 } = 4 x ^ { 2 } + 4 y ^ { 2 }$