How long should it take to copy 1gb file over the internet?

My home internet is 30mbps download and 8mbps upload.  (which I have verified using speedtests)

I use a Windows desktop PC and laptop at my office.  The internet speed there is 12mbps download.

How many minutes should it take to download a single 1gb file from my My Cloud drive to my laptop over the internet?

Thanks!

The absolute fastest would be 17 mintues.   Realistically probably about 25-30.