Can you explain what a tariff shift is$,$ using a product example and rules of origin?

Annex $4-$B refers to Product$-$Specific Rules of Origin $($PSRO$).$ Could you explain what that means?

What does it mean when a shipment's value is below the de minimis threshold and doesn't require a certificate of

origin? Can you explain this with examples for each country?

Could you discuss with examples the four criteria under Article $4\mathrm{.}2$ of the CUSMA agreement that goods must

meet to qualify as originating?

Let's say AG Impex Canada Inc. imports computer parts from China and Thailand valued at $C$$$68\mathrm{.}50$ and $C$$$42\mathrm{.}50,$

respectively. These parts are used to manufacture computers that retail for $C$$$325\mathrm{.}00.$ Can you calculate whether

Does the computer qualify as originating using the Regional Value Content $($RVC$)?$

Who is authorized to complete the CUSMA certificate of origin and what languages are accepted by customs