自行车的构造我们很熟悉，其中很多地方用到了我们所学的物理知识；请指出两处并说出相

数字化彩色多普勒超声仪的关键技术是（）。

A.宽频加变频探头

B.二次谐波成像技术

C.数字或波束形成仪

D.多道电子开关选择发射和接收的振子

E.预置多种优化检查条件

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

   小题1:     

Most fitness advice is aimed at a general audience. But if you’re an older adult, the International Council on Active Aging (ICAA) has some tips for seniors to get started and keep them at the top of their game.

   小题2:   Talk with your doctor about getting permission to begin a fitness program and making any changes to suit your situation.

  小题3:     Before starting, pick a program you’ll enjoy, so you’ll do it regularly. Check out the facility and the staff. Is the place friendly? Can you change clothes comfortably? Are facilities easily accessed?

Determine your participation style. Choose what’s best for you — a class or going solo? Morning or night hours?    小题4:   

Start slowly. Most people are overeager and sometimes overdo it. Record a baseline of your regular activities and determine a reasonable plan.

Make a date. Find a friend to exercise with you and keep you motivated.

Set specific short-term and long-term goals. Plan for activity in your day and make it a priority.

Remind yourself what your goals are. If it hurts, don’t do it.    小题5:   And once you’ve reached your goal, treat yourself for the good job you’ve done, so it will encourage you to continue.

A．Make a list.

B．Exercise Tips for Seniors to Start a Healthy Game

C．Know your choice.

D．Learn to work around pain, not through it.E.Indoor or outside exercise?

F.All the Seniors Should Be Careful Before Exercise

G.Get a thorough examination.

下列哪一项不符合地方性斑疹伤寒（）

A.其病原为莫氏立克次体

B.其病原为普氏立克次体

C.鼠为主要传染源

D.鼠蚤为传播媒介

E.发热病程一般为9~14天

下述关于随机误差对测验影响的说法中正确的是（）。

A．影响测验的信度，但不影响效度

B．影响测验的效度，但不影响信度

C．影响测验的信度，也影响其效度

D．对测验的信度、效度均无影响

以下叙述中错误的是( )。

A．对于double类型数组，不可以直接用数组名对数组进行整体输入或输出

B．数组名代表的是数组所占存储区的首地址，其值不可改变

C．当程序执行过程中，数组元素的下标超出所定义的下标范围时，系统将给出“下标越界”的出错信息

D．可以通过赋初值的方式确定数组元素的个数