As per the question the mass of the object is given as 70 kg.
The height of the object from ground is 8 m.
We are asked to calculate the potential energy of that object.
The potential energy of a object is the energy gained by the body due to its position or configuration. The energy due to the position of object from the surface is called gravitational potential energy .
If a body of mass m is at a height of h from the ground,then its potential energy is calculated as -
potential energy
![[P.E]= mgh](https://img.qammunity.org/2017/formulas/physics/high-school/xgme3zdbye2up4lnwn1zcbjsoqraw5s7zq.png)
where g is the acceleration due to gravity.
we have been given h= 8 m and m= 70 kg
we know that acceleration due to gravity g =9. 8 m/s^2
⇒

=5488 Joule
Here Joule is the unit of energy.