Which two ways does Magento persist category relationships in the database? (Choose two.)

You are creating a new page layout for your custom module.
What is the primary difference between container and block elements?

A merchant gives you the module MyCompany_MyModule to install.
How do you identify which REST endpoints are supported by the module?

You are facing a bug, which is supposedly caused by the customization of
\Magento\Catalog\Api\ProductRepositoryInterface::save().
To resolve the issue, you decide to find all logic which customizes this method. Which two places do you search for customization declarations? (Choose 2)

How many shipping addresses may be selected for an order during the checkout process?