A decision at the marginVan is a hard-working college senior. One Thursday, he decides to work nonstop until he has answered 200 practice problems for his economics course. He starts work at 8:00 AM and uses a table to keep track of his progress throughout the day. He notices that as he gets tired, it takes him longer to solve each problem. Time Total Problems Answered8:00 AM 09:00 AM 8010:00 AM 14011:00 AM 180Noon 200The marginal, or additional, gain from Van’s first hour of work, from 8:00 AM to 9:00 AM, isproblems. The marginal, or additional, gain from Van’s second hour of work, from 9:00 AM to 10:00 AM. The marginal gain from Van’s third hour of work, from 10:00 AM to 11:00 AM, isproblems. Later, the teaching assistant in Van’s economics course gives him some advice. "Based on past experience," the teaching assistant says, "working on 30 problems raises a student’s exam score by about the same amount as reading the textbook for 1 hour." For simplicity, assume students always cover the same number of pages during each hour they spend reading. Given this information, in order to use his 4 hours of study time to get the best exam score possible, how many hours should he have spent working on problems, and how many should he have spent reading?a. 1 hour working on problems, 3 hours reading. b. 2 hours working on problems, 2 hours reading. c. 3 hours working on problems, 1 hour reading. d. 4 hours working on problems, 0 hours reading.

1. revising for conciseness - eliminating flabby expressions,limiting long lead-ins, and dropping unnecessary fillerstime is money in any business environment. people want information communicated quickly and clearly. to make your writing more concise and understandable, avoid flabby expressions, long lead-ins, and unnecessary fillers. your audience will appreciate your brevity.1. if your writing contains a flabby expression like in view of the fact that, replace it with the word because / although / probably .for each of the following two sentences, choose the best revision.2. i am sending you this letter to inform you that we have experienced an unexpected surprise within our expense sheet, but we are positively certain we will solve it.1) we need to inform you that we have experienced an unexpected surprise with our expense sheet, but we are midway to an end result.2) we have identified a problem with our expense sheet, but we will solve it.3) i am sending you this letter to inform you that we have a problem with our expense sheet, but we are positively certain we have a solution.3. it is the user who should contact the center.1) everyone knows that it is the user who should contact the center.2) the user should contact the center.3) if there is a problem, the user should contact the center.read the following passage, and then answer the question.[1] you scheduled seven conference calls for this morning between 10 and 11 a.m. [2] generally, the company limits the number of conference calls to three per hour. [3] i’m letting you know that in the future, we should be more careful about scheduling.4. which revision limits the long lead-in in sentence 3? 1) in the future, we should be more careful about scheduling.2) i’m letting you know so that in the future we are more careful about scheduling calls.3) so that you know in the future, we should be more careful about scheduling.