15 $\frac{m}{s}$ = ___

The correct option is B

54 $\frac{km}{h}$

We know,1 $\frac{km}{h}$ = $\frac{5}{18}$ $\frac{m}{s}$

$\Rightarrow$ 1 $\frac{m}{s}$ = $\frac{18}{5}$ $\frac{km}{h}$

Now 15 $\frac{m}{s}$ = 15 $\times$ 1 $\frac{m}{s}$

= 15 $\times$ $\frac{18}{5}$ $\frac{km}{h}$

= 3 $\times$ 18 $\frac{km}{h}$

= 54 $\frac{km}{h}$