Final answer:
The prime meridian and the 180th meridian are opposite halves of the same great circle.
Step-by-step explanation:
The statement is True. The prime meridian and the 180th meridian are opposite halves of the same great circle. The prime meridian is defined as the line of longitude that passes through the Royal Observatory in Greenwich, England (0 degrees longitude), and the 180th meridian is known as the International Date Line. The International Date Line is opposite the prime meridian and marks the start of each day.