Why is it difficult to construct a practical calendar based on the Moon’s cycle of phases?

Explain the origin of the leap year. Why is it necessary?

Is the ecliptic the same thing as the celestial equator? Explain.

Consider a calendar based entirely on the day and the month (the Moon’s period from full phase to full phase). How many days are there in a month? Can you figure out a scheme analogous to leap year to make this calendar work?

The Great Pyramid of Giza was constructed nearly 5000 years ago. Within the pyramid, archaeologists discovered a shaft leading from the central chamber out of the pyramid, oriented for favorable viewing of the bright star Thuban at that time. Thinking about Earth’s precession, explain why Thuban might have been an important star to the ancient Egyptians.

Describe a practical way to determine in which constellation the Sun is found at any time of the year.

Explain why the year 1800 was not a leap year, even though years divisible by four are normally considered to be leap years.

Explain how the zodiacal constellations are different from the other constellations.

Please do not make joke on this question.. I have asked 3 times and get wrong answer