28 weeks is 7 months.
18 months
about 4.6 months
9 months
3 months
469 days 16 months & 3 weeks
About 14 months and a week.
Months are generally 30 or 31 days long with 7 days in a week. That makes each month a little over 4 weeks long. 39 weeks would be almost 10 months or 9 months and 3 weeks.
The whole period takes about 9 months.
8 and 1/2 months
Four months and one week.
9 months