A charged particle of mass $m=1kg$ and charge $q=2\mu C$ is thrown from a horizontal ground at an angle $\theta ={45}^0$ with speed $20m/s$. In space a horizontal electric field $E=2\times {10}^7$V/m exists along the horizontal component of the velocity of the particle. Find the range on horizontal ground of the projectile thrown.(g=10m/s²)