Have you always wondered what the difference is between a violin and a viola? Or pondered exactly who it is that has to completely overhaul a museum’s galleries between exhibits? Or puzzled over how exactly that dancer is able to hold that other dancer in the air by her big toe without either of them sustaining serious injury? Well, the Milwaukee Journal Sentinel is here to help: from now until August 1, the paper’s arts section is accepting all the questions about the arts that you’ve never asked for fear of sounding stupid. And they promise to answer them, too. Go on – you know you’ve got one…