Hannah allowed her friend Carol to borrow her laptop computer for a week during Thanksgiving Break. During that time Carol, without permission from Hannah, sold the laptop to a friend in one of her classes. When Hannah and Carol returned from the break Carol told her that she had sold the laptop because the amount offered by the buyer was "too good to pass up." She then gave the money to Hannah, who said "WOW" and "THANK YOU" and kept the money. Based on these facts is the contract of sale valid against Hannah?

Yes, these facts  are valid against Hannah which comes under Ratification Doctrine.

Explanation:

Here in the question its given that Hannah had allowed her friend to lend her computer for a one week period which was during her thanks giving break.

During those times Carol sold that laptop to a friend which was one of them in their class without asking hannah about this.

Now when after the break hannah and carol both return then carol told her that she had sold her laptop because she was getting an amount from the buyer which was too good to pass up so shesold it that moment.

Now when she gave that money to Hannah she instead of scolding her thanked her and her expression was seeming to be like she had done an awsome job for her.

So, based on the facts the contract was valid because it came under Ratification Doctrine.

decrease in total operating income of $45,000