A parallel-plate capacitor of capacitance 40F is connected to a 100 V power supply. Now the intermediate space between the plates is filled

A parallel-plate capacitor of capacitance 40F is connected to a 100 V power supply. Now the intermediate space between the plates is filled with a dielectric material of dielectric constant K = 2. Due to the introduction of dielectric material, the extra charge and the change in the electrostatic energy in the capacitor, respectively, are – 

(1) 2 mC and 0.2 J 

(2) 8 mC and 2.0 J 

(3) 4 mC and 0.2 J 

(4) 2 mC and 0.4 J                                        (JEE-2025)