The constructor function for \Magento\Catalog\Model\Category contains this excerpt:

With the automatic dependency injection that Magento provides, how is the StoreManagerInterface resolved?

You have created a module controller that responds to the following URL: /mycompany/product/load/id/123.
Which two methods will load the product model by ID as specified in the URL? (Choose two.)

How do you persist an entity to the database?

You are working on a Magento store which will be selling in two countries. Each country has its own set of payment methods.
How do you organize the project to support this requirement?

In a code review of a merchant's site you have discovered that there are multiple observers for the checkout_submit_all_after event. After closer inspection, you notice one of these observers is relying on the others being executed before it is called.
What risk does this pose, and how can it be mitigated?