问题 单项选择题

通常人们所说的一个完整的计算机系统应包括( )。

A.运算器、存储器和控制器
B.计算机的外围设备
C.系统软件和应用软件
D.计算机的硬件系统和软件系统

答案

参考答案:D

解析: 计算机系统的内容
计算机系统由硬件系统和软件系统组成。计算机硬件系统是指组成一台计算机的各种物理装置,它们由各种具体的器件组成,是计算机进行工作的物质基础。计算机硬件系统由输入设备、输出设备、运算器、存储器和控制器五部分组成。

阅读理解

       Parents and doctors have the same worry over especially low birthweight newborns.1.________A trend has therefore developed to make special formulas (配方) of extra nutrients and proteinrich foods for these tiny babies.Unfortunately,a British study has found that this practice could have negative long term effects,such as high blood pressure in adulthood.

       Between 1993 and 1995,Atul Singhal of the Institute of Child Health and his colleagues researched 299 fullterm newborns,each of whom weighed very little for their age.The babies' moms had decided not to breastfeed (用母乳喂养).

       2.________The rest received a formula with more nutrients and 28 percent more protein than the standard formula.The growth of all of these children was compared to that of 175 similarly low birthweight babies whose mothers had chosen to breastfeed their children for their first 9 months.3.________They found 83 babies from the normalformula group,70 babies from the extraformula group,and 95 babies from the breast fed group.4.________According to the latest data,children who had received the extra formula had significantly higher blood pressures than those in the other two groups.

      Seven human tests have indeed shown that when infants are overfed before being stopped breastfeeding,they have an increased possibility to become fat as youngsters.

      No matter how big a child is at birth,he or she will probably reach the same adult height no matter how quickly the baby grows.But reaching one's adult size at a slowtomoderate speed may have a lot of benefits,as Singhal says.5.________

A.Half of these children were given a normal infant (幼儿) formula for 9 months.

B.When they grow up,they might have high blood pressure.

C.These babies have very little energy because they are so small.

D.Six to eight years later,the researchers gave the children a series of measurements and tests.

E.The results were quite surprising.

F.Tiny babies will grow much slower if they are not specially fed.

G.His advice to parents:Be patient.Don't rush a child's growth.

单项选择题