Little Green will turn around and try to identify the source of the noise:

knowledge - (d20+14)[18]
knowledge - (d20+14)[29]
knowledge - (d20+14)[32]
knowledge - (d20+14)[16]
knowledge - (d20+14)[28]
knowledge - (d20+14)[17]
knowledge - (d20+14)[26]
knowledge - (d20+14)[28]
knowledge - (d20+14)[32]
knowledge - (d20+14)[17]
knowledge - (d20+14)[27]
knowledge - (d20+14)[27]

those are for the 10 knowledge skills listed in order of their appearance in the PHB, then pisionics at #11 and Incarnum at #12