24. Take the choice of which kind of soup to buy. There's too much data here for you to struggle with: calories, price, salt content, taste, packaging, and so on. If you were a robot, you'd be stuck here all day trying to make a decision, with no obvious way to trade off which details matter more. To land on a choice, you need a summary of some sort. And that's (that) the feedback from your body is able to give you.

Thinking about your budget might make your palms sweat, or your mouth might water thinking about the last time you consumed the chicken noodle soup, or noting the excessive creaminess of the other soup might give you a stomachache. You (stimulate) your experience with one soup, and then the other.

Your bodily experience helps your brain to quickly place a value on soup A, and another on soup B, allowing you to (top) the balance in one direction or the other. You don't just (add) the data from the soup cans, you feel the data.

29. Trying to produce everything yourself would mean you are using your time and resources to produce many things (which) you are a (low-cost) (consumer).

This would translate into (higher) production and income. For example, even though most doctors might be good at record keeping and arranging appointments, it is generally in their interest to hire someone to perform these services.

The time doctors (used to) keep records (are) time they (could spend) (see) patients.

Because the time spent with their patients (are) worth a lot, the opportunity cost of record keeping for doctors will be (low).

Thus, doctors will almost always find it (advantageously) (hiring) someone else to keep and manage their records. Moreover, when the doctor specializes in the provision of physician services and hires someone who has a comparative advantage in record keeping, costs will be (higher) and joint output (smaller) than would otherwise be achievable.

30. Our culture is biased toward the fine arts—those creative products that have no function other than pleasure. Craft objects are less worthy; because they serve an everyday (pleasure), they're not purely creative. But this division is culturally and historically (absolute).

Most (temporary) high art began as some sort of craft. The composition and performance of (which) we now call "classical music" began as a form of craft music (satisfied) (requiring) functions in the Catholic mass, or the specific entertainment needs of (loyal) patrons.

For example, chamber music really was designed to be performed in chambers—small intimate rooms in wealthy homes—often as background music. The dances composed by famous composers from Bach to Chopin originally did indeed accompany dancing. But today, with the contexts and functions they were composed for (going), we listen to these works as fine art.

31. Psychologists Leon Festinger, Stanley Schachter, and sociologist Kurt Back began to wonder how friendships form. Why do some strangers build lasting friendships, while others struggle to get past basic platitudes? Some experts explained that friendship formation could be traced to (infant), (which) children acquired the values, beliefs, and attitudes that would bind or separate them later in life.

But Festinger, Schachter, and Back pursued a different theory. The researchers believed that physical space was the key to friendship formation; that "friendships are likely to develop on the basis of brief and (active) contacts (making) (to go) to and from home or walking about the neighborhood."

In their view, it wasn't so much that people with similar attitudes became friends, but rather that people who passed each other during the day tended to become friends and so came to (adapt) similar attitudes over time.

34. The whole history of mathematics is one long sequence of taking the best ideas of the moment and finding new extensions, variations, and applications. Our lives today are totally different from the lives of people three hundred years ago, mostly owing to scientific and technological innovations that required the insights of calculus. Isaac Newton and Gottfried von Leibniz independently discovered calculus in the last half of the seventeenth century. But a study of the history reveals that mathematicians had thought of all the essential elements of calculus before Newton or Leibniz came along. Newton himself acknowledged this flowing reality when he wrote, "If I have seen farther than others it is (why) I have stood on the shoulders of giants." Newton and Leibniz came up with their brilliant insight at essentially the same time because it was not a huge (reap) from what was already known. All creative people, even ones who are considered geniuses, start as nongeniuses and take baby steps from there.

36. Without money, people could only barter. Many of us barter to a small extent, when we return favors. A man might offer to mend his neighbor's broken door in return for a few hours of babysitting, for instance. Yet it is hard to imagine these personal exchanges (work) on a larger scale.

What would happen if you wanted a loaf of bread and allyou had to trade was your new car? Barter depends on the double coincidence of wants, (which) not only (the other person happens) to have what I want, but I also have what he wants. Money solves all these problems.

There is no need to find someone who wants (that) you have to trade; you simply pay for your goods with money. The seller can then take the money and buy from someone else. Money is transferable and deferrable―the seller can hold on to it and buy when the time is right.

40. Intergroup contact is more likely to (increase) stereotyping and create favorable attitudes if it is backed by social norms that promote equality among groups.

If the norms support openness, friendliness, and mutual respect, the contact has a greater chance of changing attitudes and reducing prejudice than if they (are) not. Institutionally supported intergroup contact―that is, contac sanctioned by an outside authority or by established customs―is more likely to produce positive changes than unsupported contact.

Without institutional support, members of an ingroup may be (willing) to interact with outsiders because they feel doing so (to be) (acceptable) or simply inappropriate.

With the (absence) of institutional support, however, contact between groups (is) more likely to be seen as appropriate, expected, and worthwhile.

For instance, with respect to desegregation in elementary schools, there is evidence that students were (less) highly motivated and learned (less) in classes conducted by teachers (본문내용임. that is, authority figures) who supported rather than opposed desegregation.