Answer:
The value is 
Explanation:
From the question we are told that
The charge acquired on each plate is 
The additional charge accumulated on each plate is 
Generally the capacitance of the capacitor before a dielectric slab is inserted is

=> 
Generally the total charge on each plate of the capacitor when the dielectric slab was inserted is

=> 
=> 
Generally the capacitance of the capacitor after a dielectric slab is inserted is mathematically represented as

Generally the dielectric constant is mathematically represented as

=> 
=> 