The magnetic induction at a point P which is at a distance 4 cm from a long current carrying wire is `10^(-8 )` tesla. The field of induction at a distance 12 cm from the same current would be ...............tesla.
Options:
(a) `3.33xx 10^(-9)`
(b) `1.11xx 10^(-4)`
(c) `3 xx10^(-3)`
(d) `9 xx10^(-2)`