Kevin has clearly demonstrated a difficulty known as memory retrieval.
Memory retrieval is the practice of recalling knowledge that has been stored in long-term memory.
Memory retrieval may be classified into two types:
Information is retrieved from memories with the use of the recall method. However, in recognition, the expression of familiar external stimuli gives a cue that the information has been seen before.
Thus, the inability of Kevin to recall, accurately process, and store chemical formulas in his textbook clearly demonstrated a difficulty known as memory retrieval.
Learn more about memory retrieval here:
https://brainly.com/question/26544650