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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 $x(3t)$:

1. The complex Fourier series coefficients of $x(3t)$ are ${a_{k}}$ where $k$ is integer valued
2. The complex Fourier series coefficients of $x(3t)$ are ${3a{k}}$ where $k$ is integer valued
3. The fundamental angular frequency of $x(3t)$ is  $6\pi$ rad/s

For the three statements above, which one of the following is correct?

1. Only II and III are true
2. Only I and III are true
3. Only  III is true
4. Only I is true