如果债券的利息在到期时间内平均支付，支付的频率加快，债券价值就会（）。 A．上升 B
题型：单项选择题
问题：
如果债券的利息在到期时间内平均支付，支付的频率加快，债券价值就会（）。
A．上升
B．下降
C．不变
D．不一定
题型：单项选择题
There seems never to have been a civilization without toys, but when and how they developed is unknown．They probably came about just to give children something to do．
In the ancient world, as is today, most boys played with some kinds of toys and most girls with another．In societies where social roles are rigidly determined, boys pattern their play after the activities of their fathers and girls are being prepared, even in play, to step into the roles and responsibilities of the adult world．
What is remarkable about the history of toys is not so much how they changed over the centuries but how much they have remained the same．The changes have been mostly in terms of craftsmanship, mechanics, and technology．It is the universality of toys with regard to their development in all parts of the word and their persistence to the present that is amazing．In Egypt, America, China, Japan and among the Arctic（北极的） people, generally the same kinds of toys appeared．Variations depended on local customs and way of life because toys imitate their surrounding．Nearly every civilization had dolls, little weapons, toy soldiers, tiny animals and vehicles．
Because toys can be generally regarded as a kind of 
art form, they have not been subject to technological leaps that characterize inventions for adult use．The progress from the wheel to the cart to the automobile is a direct line of ways up．The progress from a rattle （拨浪鼓） used by a baby in 3,000 BC to one used by an infant today, however, is not characterized by inventiveness．Each rattle is the product of the artistic tastes of the times and subject to the limitations of available materials．
71．The reason why the toys moat boys play with are different from those that gills play with is that _____.
A．their social roles are rigidly determined
B．they like challenging activities
C．most boys would like to follow their fathers' professions
D．boys like to play with their fathers while girl with their mothers
72．One aspect of "the universality of toys" lies in the fact that _____．
A．the basic characteristics of toys are the same all over the world
B．technological advances have greatly improved the durability of toys
C．the exploration of the universe has led to the creation of new kinds of toys
D．the improvement of craftsmanship in making toys depends on the efforts of universities
73．Which of the following is the author's view on the historical development of toys?
A．Toys are playing an increasingly important role in shaping a child's character．
B．The toy industry has witnessed great leaps in technology in recent years．
C．The craftsmanship in toy - making has remained essentially unchanged．
D．Toys have remained basically the same all through the centuries．
74．Regarded as a kind of art form, toys _____．
A．reflect the pace of social progress
B．are not characterized by technological progress
C．follow a direct line of ascent
D．also appeal greatly to adults
75．The author uses the example of a rattle to show that _____．
A．it often takes a long time to introduce new technology into toy - making
B．even the simplest toys can reflect the progress of technology
C．even a simple toy can mirror the artistic tastes of the time
D．in toy - making there is a continuity in the use of materials