Classify each of the following items into the three $(3)$ types of manufacturing cost.

Tir

$\backslash$table$[[$Wubing used in manufacturing bicycles,$],[$Maintenance on machinery,Classification$],[$Electricity used in factory operations,$\backslash$table$[[$Direct labour$],[$Direct material$],[$Manufacturing overhead$]]],[$Gold used by a jewellery manufacturer,$],[$Salary of a nurse in a factory first$-$aid station,$]]$