An insulating sphere of radius a, centered at the origin, has a uniform volume charge densityrho.
A spherical cavity is excised from the inside of the sphere. The cavity has radius \frac{a}{4} and is centered at position h_vec, where |\vec{h}|<\frac34 a , so that the entire cavity is contained within thelarger sphere. Find the electric field inside the cavity.
Express your answer as a vector interms of any or all of rho, epsilon_0, r_vec, and h_vec.