A normal year has 365 days. If the two years are normal, 365+365 = 730 day.Every four years, there is an year with 366 days. If one of the year is this kind of year, the total would be 731 days. The...
If you think about it for, oh, one or two seconds - there are 4 quarters in a whole of anything, be it years, dollars, football games ... So two years would have 2 x 4 = 8 quarters.