Ok so let me explain this. <span>In the library of congress system of classifying books, every book receives a classification number that starts with 1-3 letters. Those letters give you a general idea of topic.</span><span> The "Teaching New Math" book It's in the Q's for sciences, and more specifically QA's under math. So the answer you will be looking for is QA. Hope this can help you</span>
Answer:
is d
Explanatiion : usa test prep its the answer
Explanation:
led to economic depression
