Tear a sheet in half. Make test strips with a Multigrade 0 filter on one half, Multigrade 5 on the other. Develop to completion. The contrast differences between the best exposures on each test strip (which will not necessarily be the same absolute exposure, as Grade 5 is half the speed of Grade 0) will be impressive if it's variable contrast.
Incidentally, if it's Kodak it won't be Multigrade (capital letter) as this is an Ilford trademark (and an Ilford invention).
Cheers,
R.