What have you done? You are covered in flour.

[GeneD]

What have you done? You are covered in flour.

I would use the present perfect continuous in the first sentence (What have you been doing?). In fact, I remember a similar example from a grammar book in which the continuous form is used (Kate's clothes are covered in paint. She's been painting the ceiling.), and the explanation was as follows: "We are interested in the activity. It doesn't matter if something has been finished or not". Does it mean that either the present perfect simple or continuous can be used in the two seemingly similar examples? What tense would you use?

 

[GoesStation]

The present perfect expresses exasperation in the first sentence, which is an exclamation. (Such sentences are often punctuated with exclamation marks.) The continuous tense would express simple curiosity.