A hollow conducting sphere with an outer radius of 0257m

Question

Solve the all given parts of following question:

Question: A hollow, conducting sphere with an outer radius of 0.257m and an inner radius of 0.209m has a uniform surface charge density of +6.64 × 10⁶ C/m². A charge of -0.710µC is now introduced into the cavity inside the sphere.

Part I: What is the new charge density on the outside of the sphere?

Part II: Calculate the strength of the electric field just outside the sphere.

Part III: What is the electric flux through a spherical surface just inside the inner surface of the sphere?

I need help to find the electric flux through a spherical surface just inside the inner surface of the sphere.