When julia goes to the first class of her operations management course, she finds out that in addition to the textbook she already purchased, she also needs a copy of the book the goal. at which stage of the consumer buying decision process is julia?

She is at the problem recognition stage. In this stage, the buyer recognizes that there is a deficit between what they have and what they are looking to purchase. The state they are in is less than (or substandard to) the state or item they desire to have.