第19题 (2.0) 分 “未有天地之先，毕竟是先有理”，这是一种（ ） A、朴素唯物主义观点 B、客观唯心主义

B。此题中的“天地”代表物质，“理”应是和朱熹口中的“理”是一样的，是一种客观精神，那么这句话的意思是：在没有物质之前就存在一种客观精神了。典型的意识第一性观点，是唯心的且是客观的

以The Most Unforgettable person I Ever know为题目写一篇不少于100词的作文

In my life I have met a great many people who are really worth recalling. But perhaps the most unforgettable person I ever know is my English teacher. What frequently brings back memories of my school teacher is his special qualities. First and foremost, he gave us the greatest gift a teacher can offer—an awakening of a passion for learning. He not only led us to an appreciation of the beauty and perfection of English language and literature, but also aroused our great interest in exploring something deeper in this field. Furthermore, I was attracted by his lively wit. I remember that we students always anticipated his class with great eagerness because his lecture were humorously delivered, never failing to provoke chuckles or loud laughs. Although it is nearly two years since I attended his last class, he is the talk of our old classmates, and I know part of him has already stayed in my heart. 

谁告诉我一些快乐传真游戏的题目

一箭双雕、垂头丧气、口是心非、亡羊补牢、十拿九稳、坐井观天、闻鸡起舞、呆若木鸡、鸡鸣狗盗、猫哭老鼠、一鸣惊人、树大招风、一口吃个大胖子、枪打出头鸟、放下屠刀立地成佛、杯弓蛇影、猪八戒背媳妇、猴子捞月、二龙戏珠、肉包子打狗有去无回、掩耳盗铃、嫦娥奔月、小鸟依人、关公门前舞大刀、月亮代表我的心、金鸡独立、猴子捞月

大学物理题，急急急如图示两相干波源S1和S2相距λ／4（λ为波长）

首先设点S1相位为φ1 S2相位为φ2 设在S1外侧有一点p 那么P点相对S1的相位差为X1＝ φ1-S1P×2π／2λ 同理可得P点相对S2的相位差 X2又因为 φ1-φ2＝π/2 S1- S2＝λ/4 则X2-X1＝π