Graphic D

Circumference (estimate): 43,170.3 km
2,439 km * 17.7 'earth slices' = 43,170.3 km

• 360º (circle) / 20.3º (central angle btwn. Manasquan & San Juan) = 17.7 'earth slices'
• 4,430 km (distance from Manasquan to Equator) - 1,991 km (distance from San Juan to Equator) = 2,439 km