问题 多项选择题

β系数可以反映()。

A.证券或证券组合对市场组合方差的贡献率

B.证券或证券组合对市场组合协方差的贡献率

C.证券或组合的收益水平对市场平均收益水平变化的敏感性

D.证券承担的系统性风险水平

答案

参考答案:A, C, D

解析:掌握证券β系数的定义和经济意义。

阅读理解

阅读理解。

     Plants grow faster if you talk to them and the effect is even better if you're a woman. Researchers at

Royal Horticultural (园艺的) Society carried out an experiment to find that the voice of a woman gardener

makes plants grow faster.

     The experiment lasted a month and by the end of the study scientists managed to discover that tomato

plants grew two inches taller when women gardeners talked to them instead of male.

     Sarah Darwin was the one of making the plants registered the best growth. Her voice was the most

"inspiring" for plants than the voices of nine other gardeners when reading a passage from The Origin of

Species. The great-great-granddaughter of the famous botanist Charles Darwin found that her plant grew

about two inches taller than the plant of the best male gardener.

     Colin Crosbie, Garden Superintendent (主管人) at RHS, said that the findings cannot yet be explained.

He presumes (认定) that that women have a greater range of pitch (音调) and tone which might have a

certain effect on the sound waves that reach the plant. "Sound waves are an environmental effect just like

rain or light," said Mr. Crosbie.

     The study began in April at RHS Garden Wisley in Surrey. Scientists started with open auditions (试听,

试演) for the people who were asked to record passages from John Wyndham's The day of the Triffids,

Shakespeare's A Midsummer Night's Dream and Darwin's The Origin of Species.

     Afterwards researchers selected a number of different voices and played them to 10 tomato plants during

a period of a month. Each plant had headphones connected to it. Through the headphones the sound waves

could hit the plants. Scientists decided to leave two plants in silence, thus to be positive that the experiment

is fair. It was discovered that plants that"listened" to female voices on average grew taller by an inch in

comparison to plants that heard male voices.

     Sarah Darwin said, "I think it is an honor to have a voice that can make tomatoes grow, and especially

fitting because for a number of years I have been studying wild tomatoes from the Galapagos Islands at the

Natural History Museum in London."

1. What does this passage mainly talk about?

A. Plants enjoy men's voices more than women's.

B. A botanical experiment in a museum.

C. Strange phenomenon at Royal Horticultural Society.

D. Voice influence on plant growing.

2. What do the underlined words mean?

A. Plants need sound as well as rain and light.

B. Sound is basic nutrition to the plant.

C. Sound has a good effect as rain or light does.

D. Plants are hungry for sound as well as rain and light.

3. What can we infer Sarah Darwin is?

A. A botanist.

B. A garden superintendent.

C. A gardener.

D. An environmentalist.

填空题