What is the lowest total resistance that can be secured by combinations of four coils of resistance `4Omega,8Omega,12Omega,24Omega`

Explanation

(A) Highest resistance `R_(s)=R_(1)+R_(3)+R_(4)`
`(4+8+12+24) Omega`
`48 Omega`
(b) Lowest resistance `R_(p)`
`(1)/(R_(p))=(1)/(R_(1))+(1)/(R_(2))+(1)/(R_(3))+(1)/(R_(4))`
`(1)/(R_(p))=(1)/(4) +(1)/(8) +(1)/(12)+(1)/(24)`
`=(6+3+2+1)/(24) = (12)/(24)`
`R_(p)= (24)/(12) = 2 Omega`