need help with these two problems

An alien spaceship traveling at 0.540c toward the Earth launches a landing craft. The landing craft travels in the same direction with a speed of 0.760c relative to the mother ship (as measured by aliens on the mother ship). As measured on the Earth, the spaceship is 0.120 ly from the Earth when the landing craft is launched. (a) What speed do the Earth-based observers measure for the approaching landing craft? 0.923 / c (b) What is the distance to the Earth at the moment of the landing craft's launch as measured by the aliens (mother ship)? 0.177 x Your response differs from the correct answer by more than 10%. Double check your calculations. |y (c) What travel time is required for the landing craft to reach the Earth as measured by the aliens on the mother ship? 0.136 x Your response differs from the correct answer by more than 10%. Double check your calculations. yr (d*) What travel time is required for the landing craft to reach the Earth as measured by Earth-based observers? 0.227 x Your response differs from the correct answer by more than 10%. Double check your calculations. yr (e*) What travel time is required for the landing craft to reach the Earth as measured by those on the landing craft? (No Response) yr A fellow astronaut passes by you in a spacecraft traveling at a high speed. The astronaut tells you that his craft is 22.5 m long and that the identical craft you are sitting in is 15.4 m long. (a) According to your observation, how long is your craft? 22.5 w m (b) According to your observation, how long is the astronaut's craft? 15.4 y m (c) According to your observation, what is the speed of the astronaut's craft relative to your craft? 219000000 x Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully.c Need Help