现有60件产品，编号从1到60，若用系统抽样方法从中抽取6件检验，则所抽到的个体编号可能是
A．5，10，15，20，25，30
B．2，14，26，28，42，56
C．5，8，31，36，48，54
D．3，13，23，33，43，53
答案：D
题目分析：根据系统抽样方法，按照一定的规则抽取样本。通常是将l加上间隔k得到第二个个体编号（l+k），再加k得到第3个个体编号(l+2k),依次进行下去，直到获得整个样本。
本题分6组，每组10 件产品，所以，所抽到的个体编号可能是3，13，23，33，43，53，选D。
点评：简单题，注意，根据系统抽样方法，按照一定的规则抽取样本。通常是将l加上间隔k得到第二个个体编号（l+k），再加k得到第3个个体编号(l+2k),依次进行下去，直到获得整个样本。
| 阅读短文，然后根据短文内容选择最佳答案。 | ||
| Cathy is 1.53 meters tall, but she is 160 pounds (磅). So she decides to lose weight from now on. She makes a plan for losing weight and puts it on the wall.
| ||
| 1. Cathy plans to run for every day. | ||
[ ] | ||
| A. twenty minutes B. thirty minutes C. an hour D. forty minutes | ||
| 2. Cathy plans to swim in the club. | ||
[ ] | ||
| A. twice a week B. once a week C. every day D. every month | ||
| 3. Cathy usually goes to work . | ||
[ ] | ||
| A. on foot B. by bike C. by bus D. by car | ||
| 4. Cathy wants to have for breakfast. | ||
[ ] | ||
| A. some rice and milk B. a glass of milk and an egg C. some milk and noodles D. some hamburgers and milk | ||
| 5. Does Cathy plan to just have fruit for supper and take a walk every morning? | ||
[ ] | ||
| A. Yes, she does. B. Sorry, I don't know. C. She has some vegetables and meat. D. No, she doesn't. |