1. 365.256days
2. Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56 minutes, and 4 seconds with respect to other, distant, stars (see below).
4. 365.25 days for Earth to orbit the Sun — a solar year. We usually round the days in a calendar year to 365. ... But approximately every four years, February has 29 days instead of 28. So, there are 366 days in the year. This is called a leap year.