Answer: 11.2 AU
Explanation:
Applying Kepler's 3rd law, we can find out the average distance of planet B to the star.
This Law states that for planets orbiting a same star, there exists a fixed relationship between the average distance to the star, and the period of his orbit around it, as follows:
K = T² / d³
So , in this case, we can write:
(da)³ / Ta² = (db)³ / (Tb)²
Solving for db:
db = ∛8³.(1170)² / 710² = ∛1390.4 = 11.2 AU
