You have been given the task of importing products from an external source. You decide to create a custom module to do this. The class handling the import creates a product for each record, sets the data on it and saves it to the database.
What do you inject into a constructor to represent each product you create?

How can you access the select query of a collection?

A custom module is performing an optimized custom query for quote items. The class applies the query customizations on the select object of a quote item collection instance.

You are tasked to resolve an issue where the query sometimes does not deliver the expected results. You have debugged the problem and found another class is also using a quote item collection and is loading the collection before the custom module. How do you resolve the issue, keeping maintainability in mind?

You need to control access to a custom controller action. How do you tell Magento about this new control option?

You need to add the Google Tag Manager (GTM) to every page. What three steps do you take to accomplish this in MyCompany_MyModule?