NARRATOR:
You will hear two students, Adam and Rosie, planning a presentation about diet and obesity.
NARRATOR:
First, you have some time to look at questions 21 to 24.
NARRATOR:
Now listen carefully and answer questions 21 to 24.
ADAM:
Right, Rosie, shall we start pulling together some ideas for our presentation on diet and obesity?
ADAM:
I could cover the experiment I carried out on whether people can distinguish ordinary sugar from artificial sweeteners.
ROSIE:
Was that the one where you served drinks containing one or the other and asked everyone to identify which they had?
ADAM:
Working out the procedure took a long time, especially because the participants couldn't be allowed to know which drink they received.
ADAM:
There were so many volunteers that recording exactly what each person had was difficult as well.
ROSIE:
And were they generally able to recognize the difference?
ADAM:
I'd expected most of them not to manage it, but the majority did.
ROSIE:
Then I could discuss my experiment on the amount of fat in nuts and whether the figure printed on the packet was reliable.
ADAM:
You crushed the nuts and added a chemical that took up the fat, didn't you?
ROSIE:
The result was troublesome because I measured far less fat than the packet stated, though I'm confident the manufacturer's figure was correct.
ROSIE:
I probably left the nuts too coarse, and the scales may not have been precise enough either.
ROSIE:
I'd like to repeat it one day.
NARRATOR:
Before you hear the rest of the discussion, you have some time to look at questions 25 to 30.
NARRATOR:
Now listen and answer questions 25 to 30.
ADAM:
So, what could we say about ways to help people lose weight?
ADAM:
Restaurants have several possibilities.
ADAM:
I read that diners tend to select dishes shown first or last on a menu more often than those in the middle.
ADAM:
If the lower calorie choices occupied those positions, customers might choose them without consciously noticing why.
ROSIE:
Food producers could surely do more to promote healthier eating as well.
ROSIE:
The calorie information on labels can be extremely difficult to interpret, and I suspect manufacturers sometimes make it that way deliberately.
ROSIE:
High calorie food often tastes better, which helps them sell more of it.
ADAM:
A pizza label might state the calories for only one quarter, making the number look reasonable, even though very few people stop after a quarter.
ADAM:
Another possibility is encouraging everyone to be more physically active.
ROSIE:
The English guidance is at least 30 minutes of brisk walking on five days each week.
ROSIE:
Around 40% of men and 30% of women claim they achieve that.
ROSIE:
Yet motion sensors show the real figures are only 6% for men and 4% for women.
ADAM:
That difference helps explain the rise in obesity.
ROSIE:
But how do you persuade people to exercise more?
ADAM:
Consider a railway station.
ADAM:
Travelers are more likely to use stairs if they reach them before the escalator, and a broader staircase lets more people take it simultaneously.
ADAM:
Small alterations to the surroundings can shape behavior without people being aware of it.
ROSIE:
And even if the effect is modest, repeating it every day makes it significant.
ADAM:
Still, I'm beginning to wonder whether exercise belongs in our presentation at all.
ROSIE:
We've already read a fair amount about it, though.
ADAM:
We have, but including it would make the topic too broad.
ADAM:
Our tutor specifically asked us to concentrate on nutritional causes and solutions.
ROSIE:
We already have plenty of material on that, and keeping to it will make the presentation more manageable.
ADAM:
What should we tackle now, then?
ADAM:
Our next lecture doesn't start for another half hour.
ROSIE:
Let's choose the material we're going to use and decide its sequence.
ROSIE:
Once that's settled, we can work out which slides to prepare.
ADAM:
Fine, let's do that.
NARRATOR:
That is the end of part three.
NARRATOR:
You now have one minute to check your answers to...
