Is this hotel ________ you said we were to stay in your letter?
A：in which
B：what
C：that
D：where
献血能够挽救更多的生命，下列有关献血的说法不正确的是（ ）
科技书9.80元/本，故事书8.50元/本，两本书共____元，两本书相差____元。
