Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34.
As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and ‘life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising.
Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M.
In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.
In line 2, the word “potential” could best be replaced by which of the following?
A.possible   
B.harmful      
C.primary
D.unknown

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Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the number blanks from 46 to 50
   Because an increasing number of people are opting to work outside the traditional office, notebook PCs are becoming more and more popular. However, you should know that notebook PCs aren't for everyone. As you (46) _____ up the pros and cons of your desktop PC with a new system, you should (47) _____ in mind that you may get better profit for your money by investing in a faster, more powerful desktop PC.
   Portability comes at a price. Leave your laptop unattended for any length of time in any sort of public place and you will quickly discover that it has been stolen. You could even lose it without any intentional neglect on your area; laptops (and all the business and personal information they contain) are easy (48) _____ for skilled thieves. So, yes, there are definitely serious security issues. Also, if you are prone to tossing your laptop around as you do your purse, workout bag or umbrella, you’ll probably break it before you get your money's worth. Guarantees are getting better and longer, but they still won’t cover a simple slip, let alone (49) _____ carelessness. So, before you (50) _____ out to get yourself the latest technological appliance, thick long and hard as to whether a notebook PC is really suitable for you.
(46) 
A.measure                  
B.count                       
C.even                        
D.weigh