Imagine a hypothetical situation in which a truck is moving relative to the ground with a velocity of 0.80c. A person riding on the truck throws a baseball at a velocity of 0.50c relative to the truck. What is the velocity of the baseball relative to a person standing on the ground?

A spaceship whose rest length is 283 m has a speed of 0.87c with respect to a certain reference frame. A micrometeorite, also with a speed of 0.87c in this frame, passes the spaceship on an antiparallel track. How long does it take this object to pass the spaceship as measured on the ship? Number Units

Two rockets moving towards each other. Rocket A moving to the right with speed 0.80c while rocket B moving to the left with speed 0.60c. The length of the two rockets are the same, that are 50m as measured by the earth observer.  i) What is the lengths of the two rockets as measured by the astronouts in their rockets? ii) What is the velocity of the rocket relative to each other? iii) If the earth observer measured the initial distance of the two rockets to be 2.52 x 1012 m apart, what are distance of the two rockets observed by observer in the rockets? iv) How long before they collide, observed by the observer in the rockets?  v) If both rockets could evacuate within 90 min (their own time), will they survive?