A hallow spherical conductor is charged with 10^-7 C of electricity. Find the potential at (1) the surface of the sphere and (2) at a distance of 0.4m from the surface of the sphere

Dear Bhat,

first of all, you need to specify the radius of the sphere, once you have done it, you can do V=kQ/r , where r is the distance from the center
at surface VkQ/R where R is radius of the sphere