Maintenance and repair 110 Automobiles 89 Computer graphics 47 Electrical engineering 39 Examinations 37 Electric circuits 36 Air conditioning 31 Motors 30 Certification 24 Computer-aided design 23 Electric equipment 23 Mathematics 22 Heating 21 Electric controllers 20 Direct current 19 Automobile mechanics 18 Safety measures 18 Trucks 17 Alternating current 16 Engineering graphics 16 Motor vehicles 16 Architectural drawing 15 Refrigeration and refrigerating machinery 15 Electric motors 14 Electronic equipment 14 Motors (Diesel) 14 Mechanical drawing 13 Data processing 12 Design 12 Design and construction 12