基调，是指稿件总的（  ）和分量。

问答题Did he kill Kennedy? It’s easy to see King, the writer and researcher, as a fellow time-traveler, hopelessly curious about what Oswald might say on tape or reveal while strolling around Fort Worth. But the past, the novel repeatedly reminds us, is obdurate. Under interrogation, it guards its darkest secrets. Weeks before the 22nd, Amberson is living below the Oswalds, and he still can’t be sure: “I tried the distance mic, standing on a chair and holding the Tupperware bowl almost against the ceiling. With it I could hear Lee talking and de Mohrenschildt’s occasional replies, but I couldn’t make out what they were saying.”

判断题与灰铸铁比较，球墨铸铁易于形成缩孔、缩松，特别是显微缩松。