The gravitational force between two objects is given by:
[tex]F=G \frac{m_1 m_2}{r^2} [/tex]
where
G is the gravitational constant
m1 and m2 are the masses of the two objects
r is their separation
In this problem, the first object has a mass of [tex]m_1=0.60 kg[/tex], while the second "object" is the Earth, with mass [tex]m_2=5.97 \cdot 10^{24}kg[/tex]. The distance of the object from the Earth's center is [tex]r=1.3 \cdot 10^7 m[/tex]; if we substitute these numbers into the equation, we find the force of gravity exerted by the Earth on the mass of 0.60 kg:
[tex]F=G \frac{m_1m_2}{r^2}=(6.67\cdot 10^{-11}) \frac{(0.60 kg)(5.97 \cdot 10^{24} kg)}{(1.3 \cdot 10^7 m)^2}= 1.41 N[/tex]
