A mint prepares metallic calendars specifying months, dates and days in the form of monthly sheets (one plate for each month). How many types of February calendars should it prepare to serve for all the possibilities in the future years?

Explanation

To determine how many types of February calendars a mint should prepare to serve all possibilities in future years, we need to consider two main factors: the day of the week on which February 1 falls and whether the year is a leap year or a non-leap year.

### Step-by-Step Solution:

1. **Identify the Days of the Week**:
- February can start on any day of the week: Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, or Sunday. This gives us a total of 7 possible starting days.

2. **Determine the Length of February**:
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