Power is a function of voltage times the volume of electrons (current). Power is the ability to do work and is measured in Watts. The higher the voltage the more power you have with the same current.
Well to find this out you need to make an equation
s+7=j
So for example if Johnny's sister is 15 then Johnny would be 22 because
s(sister's age) +7(number of years difference between their ages)=22(Johnny's age)
Canberra, hope this helped:)
I think it refers to worldwide mutual dependence between nations/countries as we depend on each other for the key things like food etc. on a worldwide level.