Narrator Listen to a part of a talk reporting a study project. What is the main research method?

[Professor]
    Well, good afternoon. In today’s session I will be sharing some of the findings of our research project from last term. First of all, a little bit about the background to the project. Our title, as you can see, is pretty straight forward: "car safety". But these days there’s a lot more to it then usual injunctions about drinking and driving or speeding. I had been interested and horrified by several newspaper reports on what people call "road rage". For example the famous incident of a man getting out of his car in parking lot and hitting the driver of a van who had overtaken him earlier. It seemed to me that there were almost as many serious problems when cars were parked...i.e, were stationary...as when they were travelling at 90 miles an hour. So I decided to make this the focus of the project.
    For our research we depended mainly on talking to individuals, asking them questions rather than using written questionnaires. We stopped people at a selected garage on the motorway over a two-day period, and asked them questions about what they’d observed or experienced themselves. Our respondents were both men and women, but the women were just slightly in the majority. We were pleased by the public’s willingness to stop and chat to us...in the end we talked to a total of 135 drivers over those two days.
    So what were our findings? Well, as you can see, 93% of respondents had had some kind of problem. A surprisingly large percentage -- 24% had had their car damaged in some way, but the main type of incident was being shouted at -- 79% had experienced that. 15% had experienced violence on their own persons...they’d actually been hit by someone. The police tended only to be informed when there was physical violence involved.
    So what strategies had people developed to ensure their own safety? Well, Let’s have a look at the figures here. First of all, it was quite striking that there were often distinct answers from the men and women. It was mainly women, for example, who said one shouldn’t ever stop to find out how to get somewhere. Whereas it was men who said you should try to avoid looking directly at other drivers. Both men and...oh sorry no...it was women who said you had to ask someone how to get to a particular destination. Then, I had thought that it would be mainly men, but both sexes made the point that it’s much safer to get keys out well in advance as you go towards your car. Men were very aware that muggers or whatever might be behinding the car. They also made the point that you should leave plenty of room when you park your car so you can make a quick gateway if you need to. Finally, locking doors at all times...men didn’t think it was quite as important as women, but both gave it a high safety rating.
Narrator Now get ready to answer some questions. You may use your notes to help you answer.
23. Why was the professor first interested in the subject?
24. What is the main research method?
25. Which of the following statements is true about the respondents?
26. What is the most common type of road rage incidents?
Narrator Listen again to a part of the lecture. Then answer the question.
[Professor]
    Let’s have a look at the figures here. First of all, it was quite striking that there were often distinct answers from the men and women.
27. What does the professor mean by saying thisΩ?
28. Who are more likely to inform someone of their expected arrival time?