Multi-choice problem: Choose from the options at the end, and answer how do you do this: to make a custom concrete base for a lamp.

pick from the following. (I). using any plastic container you like and a reamer make holes for your switch, cord, and socket. set them into place and pour in your mixed concrete. wait several hours and remove the mold. sand your cement block with waterproof 150, 600, and 800 sandpapers. (II). using any plastic container you like and a reamer make holes for your switch, cord, and socket. set them into place and pour in your mixed concrete. Remove the mold. sand your cement block with waterproof 150, 600, and 800 sandpapers.
(I).