Two coils `A` and `B` having turns `300` and `600` respectively are placed near each other, on passing a current of `3.0` ampere in `A`, the flux linked with `A` is `1.2xx10^(-4)` and with `B` it is `9.0xx10^(-5)` weber. The mutual inuctance of the system is

Options

A. `2 xx 10^(-5) `henry
B. `3 xx 10^(-1)` henry
C. `4 xx 10^(-5) ` henry
D. `6 xx 10^(-5) ` henry

Answer

B