Varying tempo

Hi, newish user here, basic question:
I’ve imported an mp3 into Audacity, have experimented with selecting/clipping and playback.
I would like to alter the tempo on the whole file, saving the new version (slowed down or sped up) as separate projects.
How do I do it?
Thanks very much in advance for help!
PS- Mac 10.6.8, Audacity 2.1.0

File > Save Project > Save Project As. Give it a new name. Poof. New Project.

That’s how it works in the current Audacity 2.3.3. If you’re in an earlier Audacity, you’ll have to look carefully at the File options.

You should try Effect > Change Tempo before you fall in love with it. Change Tempo and Change Pitch look great on paper, but don’t always sound so good In Real Life. Effect > Change Speed is the one that sounds best. That one doesn’t need to rip the sound apart and put it back together like Tempo and Pitch do.

Koz