I have a recording (MP3 file) made by an outside studio which is very short and which I want to make longer. It has no obvious breaks in the wave image, so I'm having difficulty finding the exact place to split it.  I want to take the first section after it is split and then copy and repeat it.
 
But it goes by too fast to find the exact spot to split, even when I expanded the view.  I tried to change the tempo to make it slower but it did not change.  I also tried to look at a piano roll view and a staff view, but they are both blank.  Would this be because it is an MP3, or what else am I missing?   Any suggestions as to what I should do?
 
Thanks, Don

Rather than let the transport run (at tempo) and update your view when zoomed in, try the scrub tool. When zoomed in to a level of your liking, hold J and swipe the wave form, which will play only the audio you pass over.

Another option is to use a sonogram VST (there are free ones) to see the frequency content of the wave form visually.

Yet another is to slip edit the right edge of the clip and audition the clip. A cross-fade on that end will also mitigate a possible click on that end. When slip-editted to your liking, right click the wave form and bounce to clip. Right click again and select Groove clip looping and you can drag the right edge to create as many repetitions as you want ( there is a dimple at the top/bottom of each repetition).

Staff view and Piano Roll can't do anything with audio, they only understand MIDI.
I would use the slip-edit-method that Mettelus suggests above.