Answer:

According to the Third Kepler’s Law of Planetary motion “The square of the orbital period of a planet is proportional to the cube of the semi-major axis (size) of its orbit”.
In other words, this law states a relation between the orbital period
of a body (planet Mercury in this case) orbiting a greater body in space (the Sun) with the size
of its orbit.
This Law is originally expressed as follows:
(1)
Where;
is the Gravitational Constant and its value is
is the mass of the Sun
(2)
(3)
(4)
Solving and taking into account that
:
(5)
Finally:
>>>>This is the period of revolution for the planet Mercury