Our calendar has leap years because
A. there is one more sidereal day in a year than solar days.
B. a tropical year is slightly more than 365 days.
C. there is a difference between a sidereal year and a tropical year.
D. the perihelion of Earth's orbit is slowly advancing.
Answer:B
Our calendar has leap years because
A. there is one more sidereal day in a year than solar days. B. a tropical year is slightly more than 365 days. C. there is a difference between a sidereal year and a tropical year. D. the perihelion of Earth's orbit is slowly advancing.