Five identical quintuplets leave earth when they reach the age of 21, in the year 2121. Each quintuplet goes on a spaceship journey that takes T years, as measured by a clock in each spaceship. During the journey they travel at a constant speed v, as measured on earth, except during the relatively short acceleration phases of their journey. Part A:

Rank these quintuplets on the basis of the year on earth when they return from their journey.
Rank from largest to smallest. To rank items as equivalent, overlap them.

A: T=20years, v=0.4c
B: T= 5years, v=0.2c
C: T=10years, v=0.8c
D: T=10years, v=0.4c
E: T=20years, v=0.8c

Part B:

Rank these quintuplets on the basis of their age when they return from their journey.
Rank from largest to smallest. To rank items as equivalent, overlap them.

A: T=20years, v=0.4c
B: T= 5years, v=0.2c
C: T=10years, v=0.8c
D: T=10years, v=0.4c
E: T=20years, v=0.8c