You can use Kepler's Third Law of Planetary Motion to calculate the period of revolution of the hypothetical planet. Here's how:

Kepler's Third Law:

The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

* T² ∝ a³

Where:

* T is the orbital period (in years)

* a is the semi-major axis (in Astronomical Units, AU)

Calculations:

1. Given: The semi-major axis (a) = 4 AU

2. Find: The orbital period (T)

Using Kepler's Third Law:

* T² = a³

* T² = 4³

* T² = 64

* T = √64

* T = 8 years

Therefore, the period of revolution of the hypothetical planet would be 8 years.