Justin Thyme used to run one batch each of $500$ As$,300$ Bs and $100$ Cs every month but now he runs a batch of $5$ As$,3$ Bs$,$ and $1$ C every half day with the use$$ of:

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Part $1$

A$.$

andon lights.

B$.$

push method.

C$.$

mixedminusmodel assembly.

D$.$

singleminusdigit setups.