12. Without graphing, determine if each polynomial function has line symmetry about the \( y \) -axis, point symmetry about the origin, or neither. Graph the functions to verify your answers. a) \( f ( x ) = - x ^ { 5 } + 7 x ^ { 3 } + 2 x \)
b) \( f ( x ) = x ^ { 4 } + 3 x ^ { 2 } + 1 \)
c) \( f ( x ) = 4 x ^ { 3 } - 3 x ^ { 2 } + 8 x + 1\)