Responsive resolutions depend on your selection made during placing an order. Responsive pages have break point defined for width depending on each device. So by default if you select Desktop, Tablets and Mobiles you would get a default break point of 1024px, 768px and 480px respectively. You can also select a custom resolution and define a separate break point for a custom resolution as well.
When using Bootstrap or any other framework the breakpoints will depend based on the selection of the framework and will be based on what is offered by the framework.