Requirement:
10% discount off total order for customers belongs to Canada subsidiary.
Solution:
The total amount can be updated by giving 10% discount for Canada subsidiary. From the description of task, every user from Canada subsidiary needs this feature without any other special criteria. For that need to create a promotion and give discount rate 10% in it . So that this promotion will not affect any other subsidiaries. And all other promotions which is activated for Canada subsidiary will also work. Adding image for reference.
