A farmers' market is held every Sunday from January to March of the year whose January page is shown. How many market days is that?

January 2030 starts on a Tuesday: Sundays 6, 13, 20, 27 (4). January has 31 days (+3), so February starts on Friday: Sundays 3, 10, 17, 24 (4). February has 28 days (+0), so March also starts on Friday and has 31 days: Sundays 3, 10, 17, 24, 31 (5). Total 4 + 4 + 5 = 13.