Answer:
<em>4.7 years</em>
Step-by-step explanation:
Distance of planet from Earth = 1.3 parsec
We know that 1 parsec = 3.26 light years
And a light year is the distance traveled by light in time period of 1 year.
So, Distance of planet from Earth = 1.3 3.26 = 4.24 light years
Given that, the person travels at a speed equal to 90% of the light speed.
To travel to the planet from Earth, Light takes 4.24 years.
To travel the distance , at a speed
light takes time of 4.24 years.
To travel the distance , at a speed
, the person takes time:
So, the twin on Earth ages by <em>4.7 years.</em>