An observer on Earth sees an alien vessel approach at a speed o
x 4jcp 7*kxg:qxfl 9w w)1y0aqf 0.60c. The Enterprise comes to the rescue (Fig. Below), overtaking the aliens while moving directly toward Earth at a speed of
*kl1 4xj9)qa xw0q: gpfy7xwc0.90c relative to Earth. What is the relative speed of one vessel as seen by the other? u =
c