Convert time domain signal to frequency domain

I have a time series data in the form of matrix of dimension 45000*60. I want to plot this data in frequency domain. the sampling frequency of the data is 250 Hz. What should i do? I want the x axis in hertz and not in number of samples.

[Adam]

doc fft

There are examples in the help for applying the FFT, on that page and others it links to.

[Star Strider]

I prefer the R2015a documentation for fft (link).

[Maanvi Bhatnagar]

Thank you, Adam and Star Strider.