If 1st January, 2001 was Monday, then what day of the week was it on 31st December, 2001?

If 1st January, 2024 was a Monday, then which day of the week was 1st January, 2025?

It was Sunday on January 1, 2006. What was the day of the week on January 1, 2010?

It was Sunday on Jan 1, 2006. What was the day of the week on Jan 1, 2010?

If October 10, 2023 was a Tuesday, then what day of the week was December 23, 2023?

First day of a leap year is Wednesday, then what day of the week was it on 31st December in that year?