How to calculate the distance in km between two coordinates?

Question

Yandex maps

How to get the distance in km between two coordinates using yandex map api?

Answer 1

1) In a straight line - open Wikipedia and take the formulas for the distance on the sphere.
1.1) Or take even more formulas for the distance on the sveroid.
1.2) I couldn’t in the formulas - use the ready ones .
2) By roads - build a route, and there will be a total distance.