An observer on Earth sees
, 3( gyfrr/aa4 8v8jd0zypywv an alien vessel approach at a speed of 0.60c. The Enterprise comes to the rescue (Fig. Below), overtaking the aliens while moving directly toward Earth at a speed of 0.90c relativ
fa w,8j g4yyv/vyrzrd8(3pa0 e to Earth. What is the relative speed of one vessel as seen by the other? u =
c