When a missile is shot from one spaceship towards another, it leaves the first at 0.950c and approaches the other at 0.750c . What is the relative velocity of the two ships?

The starship Enterprise approaches the Klingon home world with speed 0.6c relative to the planet. To announce its arrival, the Enterprise sends a message in a projectile that travels toward the planet with speed 0.4c relative to the Enterprise. At what speed does Klingon at the surface of the planet see the projectile approach?  Using relativistic velocity equation.

As spaceship A moves away from the earth at 0.510c, the captain observes a second spaceship (B) moving in the same direction at a speed of 0.520c relative to A. Find the speed of B relative to the earth.

12. (a) A particle is traveling through the Earth's atmosphere at a speed of 0.750c. To an earth bound observer, the distance it travels is 2.5km. How far does the particle travel in the particle's frame of reference? (b) Calculate the momentum of an electron traveling at a speed 0.985c? The rest mass of the electron is 9.11 X 10-31 kg.