Database normalization, 3 mistake [stucked] - Homework
Note: my university days are long behind me - I'm coming at this from a real-world perspective. Doesn't mean the answers are the expected ones, but may help give you an argument for your choices. A good instructor would consider such thing....


Agreed - a customer logically would be in a country, not a continent.
While TOTAL_AMOUNT is presumably the sum of QUANTITY_SHIPPED * PRICE for all  Items in an Order, I wouldn't consider it a normalization issue. It's a stored calculation. In a real system, the total amount could be impacted by discounts or coupons, and (in the other direction) by sales tax. So, it's arguably appropriate.
First, the CITY fields in customer, country, and division wouldn't necessarily match each other anyway. Second, a given city can have multiple zip codes, and a given zip code can cover multiple cities (at least in the United States). If you repeated the customer's address in the order, that would probably be considered a normalization error. (Arguably - I have had Amazon orders shipped to several different addresses....)
While a person certainly can have multiple email addresses, unless the assignment specified that you had to account for multiple email addresses, I would leave that be.
I assume each customer has one and only one sales rep, whereas each sales rep (worker_id) might have multiple customers; and, that each worker belongs to one and only one division. No need for a table in between, then. Many-to-many relationships are where you normally need some sort of mapping table to define the connections.


I assume that the tool you are using points the connections at essential random points on each table's box; if so, it's hard to be certain all the relationships are indeed set up with the correct directionality; if you haven't, I'd double-check that.

You have a salesrep_id in both customer and order. Again, real-world experience tells me that's wise (Real sales reps often move from one territory to another, and, if customers have real sales reps, you might be very interested in just who sold Customer X what, years later). However, in the context of your assignment, that might be considered a denormalization.

The only other thing that leapt out at me as I looked at the diagram was that there was no product table. I find that somewhat surprising. If there was a separate product table, then of course some of the fields in the items table would move there.