Assume that a customer's cart only includes one downloadable product.
What effect will it cause on the quote object?

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

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

A merchant tasked you to add an input field for notes to the Customer Account Information backend page.
Which three actions do you specify in a module's Data Patch to add a customer notes attribute? (Choose three.)

You are developing a module and need to add another column to a table introduced by another module MyCompany_MyModule via db schema.
How do you do that?

During a code review of a module MyCompany_PaymentCurrencies you see a configuration field declared in the file etc/adminhtml/system.xml:

What is the consequence of the attribute showInStore being set to 0?