Two moving coil meters $M_1$ and $M_2$ having the following particulars .$R_1=10\Omega ,N_1=30, A_1= 3.6 \times 10^{-3}m^2,B_1=0.25 \;T,R_2=14\Omega ,N_2=42, A_2= 1.8 \times 10^{-3}m^2,B_2=0.50 \;T$ $ The spring constant are identical for the two meters . Determine the ratio of current sensitivity ?

Question

$\begin{array}{1 1} 1.4 \\ 1.5 \\ 2.4 \\ 2.5 \end{array} $