Excuse me, how many days are there in a normal year? How many days are there in a leap year? What month in a leap year has one more day than in a normal year? How many days is it?
365, 366 days; February, 29 days
Why are there regular years and leap years
Because the earth around the sun is not exactly 365 days, but 365.25 days
365 days a year is a good calculation, so every four years there will be one more day, and the year with one more day is a leap year
Is 2100 a leap year? Why?
nothing
No, because the rule of the determination of the leap year of the Gregorian calendar is: one leap in four years, no leap in a hundred years, and another leap in four hundred years. The simple calculation method of the leap year of the Gregorian calendar (a year that meets one of the following conditions is a leap year) 1. It can be divided by four but not by 100. 2. It can be divided by 100 or 400
How to judge leap year and normal year
Divide the year by 4 to get the whole number, which is leap year, otherwise it is normal year
By the way, if it's a hundred years like 1900, it's divided by 400