题干

已知点A(0,0),B(0,4),C(3,t+4),D(3,t). 记N(t)为▱ABCD内部(不含边界)整点的个数,其中整点是指横坐标和纵坐标都是整数的点,则N(t)所有可能的值为(   )

A:6、7

B:7、8

C:6、7、8

D:6、8、9

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答案(点此获取答案解析)

C

同类题3

阅读下列材料,回答问题。

19世纪70年代,英国探险家斯坦利率一支考察队在非洲考察,与当地土著相遇。对此事件,斯坦利和当地土著酋长摩基姆巴分别有自己的叙述。

材料一  斯坦利的叙述

早8点左右,我们看到一个市场,附近停泊着许多独木舟。人们立即集合起来,从四面八方向我们逼近。我们长时间保持自制。但最后他们因我们的镇静而鼓起勇气,当某个人因此高叫“穆提”(投)、他们一齐向我们投掷木矛时,我们才被迫开枪,对他们予以回击,迫使他们惊惶逃窜……下午2点,我们从两岸树木茂密的河道中驶出……看到一支庞大的船队正停在河中央。那些船民发现我们后站起来,高声喊叫,把他们的号角吹得异常响……在5分钟里,我们全力射击,无暇顾及别的事。但最后我们意识到敌人正在距我们约200码的地方重新组织力量。我们热血沸腾。这简直是杀戮的世界,我们第一次感到我们憎恶居住在这里的这些丑陋不堪的食尸鬼们。

材料二  摩基姆巴的叙述

当我们听说那个白皮肤的人(指斯坦利)要来的时候,我们不禁惊奇地张开了嘴巴……我们对自己说,这人的皮肤是白色的,一定是从河流王国来的,他是我们在水中淹死的弟兄们中的一个。一切生命都来自水中,在水中他又找到了自己的生命。现在他要回到我们中间来,他要回家了。我们要举行一个宴会,我下令将去迎接我们的兄弟并陪伴他高高兴兴返回村庄……但是我们靠近他的小舟时,听到喊声:“土匪!土匪!”火杖向我们喷射铁雨,我们一时惊呆了……那天晚上我们回来时看到了可怕的东西:我们的弟兄死在血泊中,我们村遭到洗劫后被焚烧,水中飘满了死尸。那些强盗和杀人凶手消失了。现在请告诉我,那白人对我们公平吗?

同类题5

阅读下列短文,从每题所给的A、B、C和D项中,选出最佳选项。

Guilin is my favorite city in China because of its beauty, its waterways, its cafes, and most of all because I met my wife there. It is her hometown and we will both retire there in a few years.

Not only is Guilin a fascinating city, there are many interesting places to visit within a short drive from there. The Ling (sometimes called Lingqu) canal is the oldest canal in the world. It was built about 2,200 years ago and connects two major river systems, the Yangtze (to the east) and the Pearl River.

Longsheng Rice Terraces (龙胜梯田) is another manmade wonder that was built around 650 years ago. I have some photos of both of these places in my China Daily homepage Albums. Gudong Waterfall Park(古东瀑布) is another attraction that is worth visiting. The hike to the top of all these waterfalls isn’t very difficult and if you want, you can take a ride to the bottom on a personal rail car whose speed you can control with a brake.

If you want you can also climb up some of the waterfalls with the help of chains that are placed for the convenience of amateur climbers.

I have only been in Guilin during the winter and spring but my wife tells me it gets pretty hot in the summertime. That’s OK because I grew up in the Midwest of the US where it gets very hot and humid during the summer months. It rarely freezes in the winter and the spring and autumn are pleasant. Guilin receives a lot of rain, especially in late spring and early summer. Because of this there is lush(多汁的) plant life and many large trees in the area.

Being from California I’m used to having a car to get around. In fact, it’s practically a necessity in California. But in Guilin almost everything is within walking distance and if you need to go further, public buses are available every five minutes on the busy streets and every 10-15 minutes just about everywhere else. There are plenty of taxis too and most trips are only six yuan.

It’s a perfect place to retire.