There are five Sundays in February of a certain year. What day is October 1 of that year

There are five Sundays in February of a certain year. What day is October 1 of that year

February has five Sundays, which means that February has 29 days. February 1st and February 29th are both Sundays, which are leap years. March 1st is Monday. As long as you calculate the number of days from March 1st to October 1st, and divide by 7, the remainder is the day of the week
The answer is: Friday

February 1, 1998 is a Sunday, February 1, 2006 is a day of the week, February 1, 2009 is a day of the week, how to calculate this problem

Check the calendar to know!
As for how to calculate, it seems to be based on the leap year! I only know these! I'm sorry!

February 1, 1998 is Sunday. What day is February 1, 2006? What about February 1st, 2008?

(1) 2006-1998 = 8 (years), including 2 leap years, 365 × 8 + 2 = 2922 (days) 2922 △ 7 = 417 (weeks) A: February 1, 2006 is Wednesday. (2) 2008-1998 = 10 (years), including two leap years, 365 × 10 + 2 = 3652 (days) 3652 △ 7

February 1st, 2008 is Sunday. What day is February 1st, 2001? What day is 2009?
I can't thank you enough

February 1st, 2008 is not Friday? February 1st, 2001 is not Thursday? February 1st, 2009 is Sunday