```json
{
    "no": [19.0, 20.0, 4.0, 5.0, 7.0],
    "yes": [15.0, 18.0, 25.0, 28.0, 29.0]
}
```
Based on the given feature description, the feature "day" represents the last contact day of the month. To determine the appropriate ranges of values for this feature, we need to consider that a month generally has 30 or 31 days. Given this prior knowledge, typical day values for each target class can be identified.

For the "no" class:
- 19.0: A middle-of-the-month value that is less likely to receive a positive response.
- 20.0: Another middle-of-the-month value that is less likely to receive a positive response.
- 4.0: A value near the start of the month that is less likely to receive a positive response.
- 5.0: A value near the start of the month that is less likely to receive a positive response.
- 7.0: A value near the start of the month that is less likely to receive a positive response.

For the "yes" class:
- 15.0: A middle-of-the-month value that is more likely to receive a positive response.
- 18.0: A middle-of-the-month value that is more likely to receive a positive response.
- 25.0: A value closer to the end of the month that is more likely to receive a positive response.
- 28.0: A value near the end of the month that is more likely to receive a positive response.
- 29.0: A value near the end of the month that is more likely to receive a positive response.

Please note that these values are just examples and may vary depending on the specific dataset and context.