Answer:
3.33m
Step-by-step explanation:
Given parameters: 
Force applied =500N 
Elastic constant = 150N/m 
Unknown: 
Amount of stretch or extension = ? 
Solution: 
To solve this problem use the expression below: 
 F = k e 
F is the force applied 
k is the elastic constant 
e is the extension 
 So; 
 500 = 150 x e 
 e = 
 = 3.33m