Consider two identical cells each of emf E and internal resistance r connected to a load resistance R.Now, match the given columns and select the correct option from the codes given below.

If cells are connected in series: Eeq  =  2E,  req = 2r.Maximum power will be transferred if R=req  =2r.Then current in R:  I=EeqR+req  =  2E2r+2r =E2rPower  =  I2 R= E2r2  2r=E22rIf cells are connected in parallel: Eeq  =  E,  req = r2For maximum power: R=req  =r2,  Then current in R:I=EeqR+req  =  Er2+r2 =ErPower : I2R = Er2  r2 =  E22rHence [i - q] [ii - q] [iii - s] [iv -r]