Answer:
The magnitude of the gravitational field strength near Earth's surface is represented by approximately  .
.
Explanation:
Let be M and m the masses of the planet and a person standing on the surface of the planet, so that M >> m. The attraction force between the planet and the person is represented by the Newton's Law of Gravitation:

Where:
 - Mass of the planet Earth, measured in kilograms.
 - Mass of the planet Earth, measured in kilograms.
 - Mass of the person, measured in kilograms.
 - Mass of the person, measured in kilograms. 
 - Radius of the Earth, measured in meters.
 - Radius of the Earth, measured in meters. 
 - Gravitational constant, measured in
 - Gravitational constant, measured in  .
.
But also, the magnitude of the gravitational field is given by the definition of weight, that is:

Where:
 - Mass of the person, measured in kilograms.
 - Mass of the person, measured in kilograms.
 - Gravity constant, measured in meters per square second.
 - Gravity constant, measured in meters per square second.
After comparing this expression with the first one, the following equivalence is found:

Given that  ,
,  and
 and  , the magnitude of the gravitational field near Earth's surface is:
, the magnitude of the gravitational field near Earth's surface is:


The magnitude of the gravitational field strength near Earth's surface is represented by approximately  .
.