设等差数列的首项为a,公差为d,则它含负数项且只有有限个负数项的条件是( ) A

题型:选择题

问题:

设等差数列的首项为a,公差为d,则它含负数项且只有有限个负数项的条件是(  )

A.a>0,d>0

B.a>0,d<0

C.a<0,d>0

D.a<0,d<0

考点:等差数列的定义及性质
题型:选择题

种植花草时,经常要给它们松土、施肥、浇水、置于阳光下,天冷了还要及时将花转移到室内,而且一般一个花盆只栽一株植物.这体现了生物生存所需要的基本条件,与上述顺序相对应的是(  )

①营养物质;②空气;③阳光;④适宜的温度;⑤一定的生存空间;⑥水.

A.⑤⑥③①②④

B.①②③④⑥⑤

C.④③②①⑥⑤

D.②①⑥③④⑤

题型:选择题

男性,70岁。因患急性广泛前壁心肌梗死合并心源性休克急诊住院治疗,下列哪一药物为首选()

A.多巴酚丁胺

B.硝普钠

C.吗啡

D.多巴胺

E.速尿

题型:选择题

可诊断糖尿病的血糖水平是()。

A.空腹血糖5.5mmol/L,餐后2小时血糖7.2mmol/L

B.空腹血糖5.8mmol/L,餐后2小时血糖10.2mmol/L

C.空腹血糖6.8mmol/L,餐后2小时血糖7.5mmol/L

D.空腹血糖7.8mmol/1,餐后2小时血糖11.5mmol/L

E.空腹血糖2.7mmol/L,餐后2小时血糖3.9mmol/L

题型:选择题

Most critical plot points in Harry Potter and the Sorcerer’s Stone came from J. K. Rowling’s imagination, but Flamel and his powerful pebble were legendary long before Harry went to Hogwarts. The 14th century alchemist created the philosoper’s stone (called "sorcerer’s" in U.S.editions of Potter ), with which he turned mercury to gold and gained eternal life. But Flamel’s tale—like his stone and his science—was no more real than a magic.

The philosopher’s stone was the key to alchemy, the medieval predecessor to chemistry that aimed to cure all illnesses, make the elixir of life, and transmute base metals into gold. The last made perfect sense at the time. The Aristotelian theory of elements stated that all things consisted of fire, air, water, and earth. So a little shift in one metal’s composition could create gold.

Flamel was renowned as an alchemical success. In 1382, after 25 years of studying an ancient book by "Abraham the Jew", he is said to have produced the philosopher’s stone. His texts, notably a deconstruction of the "Abraham" work, were standard reading for aspiring scientists like Isaac Newton.

Many alchemists believed Flamel faked his 1418 death and that of his wife. Rumored sightings in the 18th century placed them at the Paris Opera. As late as 1816 there were reports of people searching Flamel’s former house for secrets of the stone.

Contemporary historians say, a Nicolas Flamel did live in Paris in the 1300s and endowed many churches and hospitals with his wealth. But he was no alchemist. "He got his money in pedestrian ways—his wife’s earlier marriages, real-estate speculation," says lawrence Principe, author of The Aspiring Adept. Anachronisms, style of language, and the lack of earlier copies indicate that none of "his" writings originated prior to the 1500s.

"This sort of thing happens in alchemy," says Bill Newman, author of alchemical history Gehennical Fire. When an alchemist couldn’t back up his ideas, he might publish them in the guise of a "lost" work. Flamel’s wealth made a good candidate for alchemical identity theft.

Flamel writings and sightings faded with alchemy’s prestige. And the closest anyone’s come to the philosopher’s stone is Rowling. In her hands, it has yielded not just gold but eternal (shelf) life as well.

The last sentence of Paragraph 6, "Flamel’s wealth" identity theft. " implies that (). "

A. Flamel’s wealth and his fame was exploited to promote alchemy

B. Flamel’s made his fortune by deceiving all people including his wife

C. Flamel’s pretended to be an alchemist and earned his living by that

D. Flamel’s success in alchemy had much to do with his wealth

题型:选择题

托收承付结算方式不能用于同城结算。( )

更多题库