Gauss's Law – Field due to a Charged Conducting Sphere

2020 1 question

1. A spherical conductor of radius 10 cm has a charge of $3.2\times10^{-7}\ C$ distributed uniformly. What is the magnitude of electric field at a point 15 cm from the centre of the sphere? ($\frac{1}{4\pi\epsilon_0}=9\times10^9\ N\,m^2/C^2$)