Answer:
sometimes harmful and sometimes beneficial
Answer:
a)
, b)
, c) 
Explanation:
a) The capacitance of two parallel plates capacitor with dielectric is given by the following expression:

Where:
- Dielectric constant.
- Vaccum permitivity.
- Plate area.
- Distance between plates.
Hence, the capacitance of the system is:



b) The charge can be found by using the definition of capacitance:




c) The energy stored in the charged capacitor is:




Answer:
3, 4, 2
Explanation:
I can't see the final ones.
It's on your exam boards specification or just google it. the foundation paper will have the same equations as higher, but higher just has more.