Answer
$\lambda=1.41\times 10^{-33}\ m$
Work Step by Step
From De Broglie's equation:
$\lambda=\frac h{m.v}$
$\lambda=6.626\times20^{-34}\ J.s\times 1\ (kg.m^2/s^2)/J\div (0.00150\ kg\times 700\ mph\times 0.447\ (m/s)/mph)$
$\lambda=1.41\times 10^{-33}\ m$
