It is given that a body of mass $m=100 \mathrm{g}$ moves at the speed of $v=36 \mathrm{km} {\mathrm{h}}^{-1}$.

The de Broglie wavelength related to it,

$\lambda ==\frac{h}{p}=\frac{h}{mv}$, here $h$ is Planck's constant and $p$ is momentum.

Substituting given values,

$\lambda =\frac{6.626\times {10}^{-34}}{0.1\times 36\times {\displaystyle \frac{1000}{3600}}}\simeq {10}^{-34}$