A merchant is interested in setting different prices for the same products in different storescopes.
What do you reply to this inquiry?

You are working on a jewelry store that sells rings. Each ring allows an adjustment in size. The customer specifies finger size in inches and the merchant physically adjusts the stocked ring to the required size.
How is this represented in Magento?

You have created a new block and will be adding this block on every page. The block contains user-specific
information and cannot be cached. The block is added to the default.xml with:

What does this accomplish?

How do you persist an entity to the database?

How do you add a foreign key to an existing table created by another module?