Discrete Math Question

[Bashyboy]

The question is, "Find the dual of each of these compound propositions."

The propositions being: p∧¬q∧¬r, (p∧q∧r)∨s, and (p∨F)∧(q∨T)

I don't quite understand what they want me to do.

 

[HallsofIvy]

Do you know what the "dual" of a proposition is?