As I said Sonar behaves a little different. I used Melodyne to tell me the BPM of the file but I could have used Reaper (slightly differently). Then I set the Reaper project file to the speed of the worst file loaded the file and changed the project speed to 105. Job done. Then added the next file.
That was the method I used for simplicity. There is a more correct way in Reaper see Kenny Gioia videos about setting track tempos.
I know I keep on about it but I find Reaper much better than Sonar for audio tracks (stretching, altering tempos, slicing and merging) and Sonar much better than Reaper for midi (notation). There are tools in Sonar for editing midi most people are unaware of that I don’t think are available in Reaper.
I find it confusing that folk will have 10 or more compressors or EQs because different VSTs behave differently and yet try to do all in one DAW. Most DAWs have slightly different features and behaviours. Different tools for different jobs. Learning to use Reaper for example will enhance your knowledge of Sonar or RealBand or BIAB even VSTs. The same is true for any DAW I am not saying Reaper will teach you more but having multiple tools for multiple jobs will teach you more. IMHO.
See
https://www.cakewalk.com/Documentation?product=SONAR%20X3&language=3&help=AudioSnap.03.html This may help to do it in Sonar.
Tony