[lrisNil]

I'm asked to draw a mechanism of the following compound dissolved in acidic water.
(Keto-Enol tautomerization)

I became confused because, what's acidic water? Is it H2O or H3O, or does it make a difference?
I was thinking I should do the nucleophilic attack on water with the electrons on the O of the compound.
..but which water is it?!

Thanks for reading this!   

[Ben Bob2]

Acidic water just means that H⁺ is present. 

[lrisNil]

Thank you Ben.