Engine: Electricity

1. A emery paper for the initial cut and crocus cloth for the finishing cut
2. B a file for cutting the approximate curvature followed by sandpaper for the final fit
3. C course lapping compound, followed by a medium and then a fine grade
4. D using fine sandpaper on a deenergized machine between the brush and the commutator to establish the proper curvature

Tip: press A-D to answer