b
(b) Reaction on inner wheel ${R_1} = \frac{1}{2}M\left[ {g - \frac{{{v^2}h}}{{ra}}} \right]$
Reaction on outer wheel ${R_2} = \frac{1}{2}M\left[ {g + \frac{{{v^2}h}}{{ra}}} \right]$
where, $r =$ radius of circular path, $2a =$ distance between two wheels and $h = $ height of centre of gravity of car.