Answer:
 98J
Explanation:
Given parameters: 
Mass of rock  = 5kg 
Height = 2m 
Unknown: 
Work done  = ? 
Solution: 
The amount of work done is given as: 
  Work done  = Force x distance 
  Work done = Weight x height
   Work done  = mgH 
Now insert the parameters and solve; 
  Work done  = 5 x 9.8 x 2 = 98J
 
        
             
        
        
        
Four regions of the electromagnetic spectrum that astronomers use when observing objects in the space are the following enumerated answers.
1. First is Ultraviolet
2. Next is Infrared
3. Then the radio
4. Lastly the Visible lights.
These are the answers to the problem.
 
        
             
        
        
        
E - impossible to determine based on the given information
        
             
        
        
        
P.E = mgh
This is the formula for potential energy.
This is where m is mass, g is the acceleration due to gravity, and h is height.
All you have to do is multiply all these numbers together.