Ships Two Ships Travel Near C Toward Each Other. What Is The Speed Of One Ship Relative To The Other?

Two ships travel near c toward each other. What is the speed of one ship relative to the other? - ships

Suppose that two ships, A and B at a sufficient distance from each other on a collision course with the other. Even travel agent, Newton was the first test, and no boat can be used as an inertial system. After an external reference point, the two ships move 0.999c.

For an observer on a ship, what is the approach velocity of B?