Read the four sentences from "Video Games in the Age of Cell Phones." [1] This equation is getting harder to balance because as more and more developers get into the market, drawn by those fat revenue numbers, they compete for a finite pool of advertising, driving up prices, with the result that user-acquisition costs are going up faster than revenues are. [2] According to one estimate by the mobile-marketing-technology firm Fiksu, the cost to acquire a loyal user was $2.74 in April, up 80% from the previous year. [3] To jack up revenue numbers, publishers have to resort to more and more aggressive business models. [4] In other words: freemium. Which statement best describes the type of evidence and its purpose as presented in Sentence 2?

Your question is incomplete because you have not provided the answer options, which are:

data, to support the claim that user-acquisition costs are rising quickly

quotation, to cite an expert opinion

fact, to support the claim that mobile users are loyal

definition, to explain what user-acquisition cost means

data, to support the claim that user-acquisition costs are rising quickly

Explanation:

Sentence two from "Video Games in the Age of Cell Phones" supports the information given in the topic sentence, which is number one. Thus, sentence two provides statistical numbers as evidence to prove that advertising costs have risen faster than profits. In that respect, it mentions that Fiksu claims to have spent $2.74 to gain a customer, a cost which is eighty per cent more expensive than the year before.

the following key ideas correctly express the key sentence.

restate key idea: most people can learn to swim in ten short lessons.

restate key idea: the majority of water-accident victims require mouth-to-mouth breathing.

restate key idea: an empty, tightly closed gallon jug will support a tired swimmer.  

restate key idea: first aid is to prevent accidents as well as assist in rescue.

explanation: the key idea needs to have the same topic as the key sentence (drowning and safety).

its c

explanation: