Your question is clear? Can you rephrase them, please?
However I can tell one thing: 'so' modifies the adjective exhausted. It is a complex sentence containing adverb clause of frequency - indicating the limit of something.
Let me know whether this explanation is relevant to your question:
Sheeba said that she was alright. Sheeba spoke so softly that noone could hear. In the first sentence ( complex) that is the conjunction and with regard to the clause, it is a noun clause.
In the second sentence ( complex) so..that is the conjunction and the clause is the adverb clause of degree.