Two pretty simple Questions.. i worked them out...  but my answers r different from the text book answers.. mayb my method was wrong.. do tell me what the right method is asap(rates assured)..show me the working...

 

1.a parallel plate capacitor connected to a 12 V source is charged to 21 microC. If the capacitor is filled with an oil of dielectric constant 3,then the charge stored is?

 

A.I got the ans as 63 microC.. but the ans is given as 57 microC.. how is it 57?

 

2.Three capacitors 2 microC,5,MicroC, and 3 microC are in parallel across 5 V

supply. the charges on each of them respectively are ?

 

A.i got the ans as 10 MicroC,25 MicroC,15 microC...but the ans is 12 microC,30 MicroC,and 18MicroC.. how is it so ?