Answer
a) Odd
b) Odd
c) Even
d) Odd
Work Step by Step
a) Symmetric to the origin.
b) Symmetric to the origin and has the parent (original) function of $x^3$. The exponent is an odd number, thus making this an odd function.
c) The parent function of the given is $x^4$, the exponent is even, thus making this an even function.
d) Despite it being a step function, because it properly reflects over the x-axis, it is an odd function.
