Final answer:
Tommy cleverly deduces the situation involving the ghost by paying attention to subtle cues, showing his quick wit and perceptiveness.
Step-by-step explanation:
Tommy uses clever thinking to get rid of the ghost by understanding the subtle cues provided to him and acting upon them in a logical manner. Despite the physical barrier of being outside with limited communication through the glass, Tommy deduces the situation surrounding the need for salt and its connection to the temperature.
This comprehension leads him to bring not only the requested item but also an often-overlooked one (pepper) after noticing a sneeze, which demonstrates his attentive and quick-witted nature. He recognizes that the sneeze indicates the need for pepper, and this level of perceptiveness ultimately resolves the unusual standoff and the mystery of the ghost. His ability to understand and act quickly is what brings the resolution to the problem.