There were 36,000 hardback copies of a certain novel sold before the paperback version was issued. From the time the first paperback copy was sold until the last copy of the novel was sold, 9 times as many paperback copies as hardback copies were sold . If a total of 441,000 copies of the novel were sold in all, how many paperback copies were sold?

【OG20-P580-669题】Rainwater contains hydrogen of a heavy form called deuterium. The deuterium content of wood reflects the deuterium content of rainwater available to trees during their growth. Wood from trees that grew between 16,000 and 24,000 years ago in North America contains significantly more deuterium than wood from trees growing today. But water trapped in several North American caves that formed during that same early period contains significantly less deuterium than rainwater in North America contains today.Which of the following, if true, most helps to reconcile the two findings?

If p is the product of the integers from 1 to 30, inclusive, what is the greatest integer k for which 3k is a factor of p?

【OG18-P387-455题】According to the passage, each of the following is a difference between women’s oral narratives and most standard histories EXCEPT:

Such orb-weaving spiders like the argiope build webs in an essentially wheel-like structure, with an outer rim and a number of spokes emanating from the hub.

【OG20-P607-754题】Vargonia has just introduced a legal requirement that student-teacher ratios in government-funded schools not exceed a certain limit. All Vargonian children are entitled to education, free of charge, in these schools When a recession occurs and average incomes fall, the number of children enrolled in government-funded schools tends to increase. Therefore, though most employment opportunities contract in economic recessions, getting a teaching job in Vargonia's government-funded schools will not be made more difficult by a recession.Which of the following would be most important to in order to evaluate the argument?

【OG20-P606-751题】NorthAir charges low fares for its economy-class seats, but it provides very cramped seating and few amenities. Market research shows that economy passengers would willingly pay more for wider seating and better service, and additional revenue provided by these higher ticket prices would more than cover the additional cost of providing these amenities. Even though NorthAir is searching for ways to improve its profitability, it has decided not to make these improvements. Which of the following, if true, would most help to explain NorthAir's decision in light of its objectives?

【OG20-P602-740题】Studies in restaurants show that the tips left by customers who pay their bill in cash tend to be larger when the bill is presented on a tray that bears a credit card logo. Consumer psychologists hypothesize that simply seeing a credit-card logo makes many credit card holders willing to spend more because it reminds them that their spending power exceeds the cash they have immediately available.Which of the following, if true, most strongly supports the psychologists' interpretation of the studies?

【OG20-P602-739题】Between 1980 and 2000 the sea otter population of the Aleutian Islands declined precipitously. There were no signs of disease or malnutrition, so there was probably an increase in the number of otters being eaten by predators. Orcas will eat otters when seals, their normal prey, are unavailable, and the Aleutian Islands seal population declined dramatically in the 1980s. Therefore, orcas were most likely the immediate cause of the otter population decline.Which of the following, if true, most strengthens the argument?

【OG20-P601-736题】Many people suffer an allergic reaction to certain sulfites, including those that are commonly added to wine as preservatives. However, since there are several winemakers who add sulfites to none of the wines they produce, people who would like to drink wine but are allergic to sulfites can drink wines produced by these winemakers without risking an allergic reaction to sulfites.Which of the following is an assumption on which the argument depends?