How many kilometers does each of meridian has?

Question

How many kilometers does each of meridian has?

Answer 1

69 miles (111 kilometers)

Answer 2

A degree of longitude is 60 nautical miles at the equator. At an arbitrary latitude L, it's 60 nautical miles times the cosine of L.

1 nm = 1.85 km, so 1 degree of longitude at the equator is 111 km.