Question

1. why does february not have 29 days every year?

the calendar year is based on the tides. every four years, february has an extra tidal cycle, which causes an extra day to be added to the calendar
every four years, the moon phases change, which causes the month of february to have an extra day.
every four years, the speed at which earth rotates on its axis increases, which causes an extra day to be added to the month of february.
it takes 365.24 days for earth to revolve around the sun. a calendar year is represented by 365 days. an extra day is added every four years to account for the 0.24 day

Explanation:

Step1: Earth's revolution period

The Earth takes approximately 365.24 days to complete one revolution around the sun.

Step2: Calendar year representation

A calendar year is set as 365 days.

Step3: Leap - year adjustment

Since \(0.24\times4\approx1\), every four years, an extra day is added (leap day) to account for the accumulated fraction of a day from the Earth's revolution period compared to the calendar year. This is why February has 29 days every four years (in a leap year) and not every year.

Answer:

It takes 365.24 days for Earth to revolve around the sun. A calendar year is represented by 365 days. An extra day is added every four years to account for the 0.24 day.