Let $x(t)$ be a continuous time periodic signal with fundamental period $T=1$ seconds.Let ${a_{k} }$ be the complex Fourier series coefficients of $x(t)$, where $k$ is integer valued. Consider the following statements about $x(3t)$:
- The complex Fourier series coefficients of $x(3t)$ are ${a_{k}}$ where $k$ is integer valued
- The complex Fourier series coefficients of $x(3t)$ are ${3a{k}}$ where $k$ is integer valued
- The fundamental angular frequency of $x(3t)$ is $6\pi$ rad/s
For the three statements above, which one of the following is correct?
- Only II and III are true
- Only I and III are true
- Only III is true
- Only I is true