417
Eight weeks.
Including January and March, it's 13 weeks. In regular years it is 12 weeks and 6 days, and in leap years it is exactly 13 weeks. If referring to the period from the beginning of January to the beginning of March or from the end of January to the end of March (or middle to middle, etc.), it is eight weeks and three days in regular years and eight weeks and four days in leap years.
14 weeks
four weeks
Eight weeks and two days
there are 211 weeks in 4 years and 3 weeks
56
There are two years in 104 weeks.
38 years, 24 weeks
681 weeks is 13.1 years.
There are 432 weeks in 9 years.
10.1 years = 526.992315 weeks