How firms avoid paying tariffs

Firms are using a variety of tricks to avoid paying tariffs Trump imposed on China (WSJ, Feb. 2020). Here are some questions.

1. What determines whether the US firm moves operations to the US, continues to import from China and pay the tariff, or use a trick to sidestep the tariff?
2. Is sidestepping the tariff consistent with the goal of moving operations to the US?
3. Are the tariffs increasing the general standard of living in the US?