Answer: 2 2/3 cups of flour
Step-by-step explanation: If one batch represents 1/4 of the total number of cookies he needs, then it can be deduced that he needs four total batches. If it requires 2/3 cups of flour for each batch and he needs 4 batches, you would multiply 2/3 by 4 to get the answer.
2/3 × 4 = 2 2/3