Consider the question. Test for natural language inference.
Premise: "A postal carrier with a big smile stands on the sidewalk with his cart of mail."
Hypothesis: "A postal carrier with a big smile  is standing on the sidewalk delivering mail."
Is the hypothesis entailed by the premise?
Options:
- yes
- no
- it is not possible to tell
 What is the step-by-step reasoning process to arrive at the answer: it is not possible to tell?
The fact that the postal carrier has mail does not mean that said mail is being delivered.