Plotting first channel in matlab

The data is sampled at 2048Hz. Plot the first channel of the data. Calculate RMS value and standard deviation of the signal using different colors on the same plot. Label axes. What can you infer from the RMS and standard deviation values?

I'm not sure how to do this. I'm assuming it means plot the first column based on what it is asking.

Will this be something like:

t = 0:64300; f = 2048; x = (:,1);

I'm lost sorry