According to the Question,

From the Question,
- Initial Acceleration,a = 5 m/s²
- Force at a = 5 m/s²,f = 25 N
- Final Acceleration,A = 9 m/s²
To find
Force exerted on the object at a = 9 m/s²
We Know that,

Firstly,we need to find the mass of the object
Thus,

Now,
