Problem: Suppose that casts are made of the shoe and tire tread impressions documented at the secondary crime scene. Using class characteristics alone, the forensic examiner is able to state that the shoe impressions came from two different shoes and that neither shared class characteristics with any of the shoes belonging to the suspect. The tire tread impressions share class characteristics with those on the suspect's truck, but the soil recovered from the tire treads on that truck does not share any of the characteristics of the soil at the burial site. Based on all the information provided in the scenario, offer several possible occurrences that could have led to this finding. Be mindful to avoid confirmation bias. For each hypothesis developed, explain what additional evidence will have to be collected to confirm or refute your ideas.