Question

why does feb has 28 days only

Answer 1

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The new months each had 28 days. But that didn't sit well with Numa because even numbers were considered bad luck at the time. So, he added a day on to January, giving the year an odd-numbered 355 days. No one knows why February was left with 28 and remained an unlucky month.

Answer 2

 is the second month of the year in the Julian and Gregorian calendars. It is the shortest month and the only month with fewer than 30 days. The month has 28 days in common years or 29 daysin leap years.February is the third month of meteorological winter in the Northern Hemisphere. In the Southern Hemisphere, February is the third month of summer (the seasonal equivalent of August in the Southern Hemisphere, in meteorological reckoning)