From January 1 to October 1, there are exactly 39 weeks. This period includes the full months of January through September, totaling 39 weeks, plus the first day of October.
It was 39 weeks.
The period is seventeen weeks and four days inclusive.
Jan 1st - Oct 31st is Forty weeks and two days - according to my Windows calendar !
1227 weeks.
21 weeks and 4 days.
21 weeks and 4 days.
34 weeks and 5 days.
34 weeks and 5 days.
From the 7th of September to the 1st of October is 3 weeks and 3 days.
52 weeks.
From January 1st 2020 to June 1st 2010 is 500 weeks and 1 day. From January 1st 2020 to June 1st 2020, which may be what you meant to ask, is 21 weeks and 5 days.
Between January 1st 2010 and May 1st 2010 there are 121 days. There are 12.7 weeks between January and May of 2010.