1. How does an NMI manifest on a Mac OS X system? A. Blue Screen of Death B. Pinwheel of death C. Interrupt of death D. NMIs only happen on Windows systems. 2. Silas has an AMD-based motherboard with two sticks of DDR2 RAM installed in two of the three RAM slots, for a total of 2 GB of system memory. When he runs CPU-Z to test the system, he notices that the software claims he’s running single-channel memory. What could be the problem? (Select the best answer.) A. His motherboard only supports single-channel memory. B. His motherboard only supports dual-channel memory with DDR RAM, not DDR2. C. He needs to install a third RAM stick to enable dual-channel memory. D. He needs to move one of the installed sticks to a different slot to activate dual-channel memory. 3. If you upgrade your memory but notice that the RAM count does not reflect the additional memory, what should you do? A. Remove the RAM and try to reinstall it. B. Restart the computer. C. Return the memory because it’s probably bad. D. Go to Setup and configure the memory to reflect the new amount. 4. What does a non-maskable interrupt cause the CPU to produce? A. The Blue Screen of Death B. A parity error C. Excessive heat D. An incorrect memory count 5. What does the CPU use to access the system’s RAM? A. The system bus B. ReadyBoost C. The address bus D. The expansion bus 6. What is the best way to determine the total capacity and specific type of RAM your system can handle? A. Check the motherboard book. B. Open the case and inspect the RAM slots. C. Check the Device Manager. D. Check the System utility in the Control Panel. 7. Which of the following PC speed ratings matches up with DDR3- 1600 RAM? A. PC3-6400 B. PC3-8500 C. PC3-10600 D. PC3-12800 8. Which of the following is a valid package size for DDR2 DIMMs? A. 168-pin B. 172-pin C. 184-pin D. 240-pin 9. What package does DDR3 SDRAM use for desktop PCs? A. 30-pin B. 168-pin C. 172-pin D. 240-pin 10. Which of the following is a valid package size for DDR4 DIMMs? A. 172-pin B. 184-pin C. 240-pin D. 288-pin 11. What happens if you mix RAM sticks of different speeds? A. Your computer will work fine as long as it uses dual-channel architecture. B. Your computer may slow down. C. Your computer will work fine if all the memory sticks are slower than the speed of the motherboard. D. Your computer may lock up every few seconds or provide corrupted data. 12. Why is SDRAM faster than regular DRAM? A. It makes two processes per clock cycle. B. It runs synchronously with the system clock. C. It uses dual-channel architecture. D. It has fewer pins, resulting in fewer corrupt bits. 13. What is true about a double-sided DIMM? A. It has memory chips on the front and back. B. It can be installed forward or backward. C. It is twice as fast as a single-sided DIMM. D. It has half the capacity of a quad-sided DIMM. 14. What is the minimum requirement for RAM for Windows 7? A. 128 MB B. 256 MB C. 512 MB D. 1 GB 15. What happens if you add two RAM sticks to your PC, and one has a bad SPD? A. When your system boots, it will recognize both RAM sticks but will not register any special features (such as ECC) of the stick with the bad SPD. B. When your system boots, it will only register the presence of the RAM stick with the good SPD. C. When your system boots, it won’t register the presence of the RAM stick with the bad SPD until you configure the RAM settings by using the Setup utility. D. When you try to boot the system, you will get a POST error message and the system will not boot.
> The lowest voltage version of DDR3 is __________ .
> The Windows tool that attempts to fix invalid filenames, erases lost clusters, and seals off bad clusters is called _________ (or chkdsk).
> In a process known as ___________ , a CPU can slow itself down in low-demand times or if it gets too hot.
> If a stock heat-sink and fan assembly can’t handle an overclocked CPU, a solution based on _________ might do the trick.
> A CPU with a _________________ can handle RAM directly.
> Divided into L1, L2, and L3, the __________ consists of a small amount of __________ that serves as a holding area. This provides data to the CPU faster than getting it from regular memory or when RAM is unavailable because of refreshes.
> Areas inside the CPU where it temporarily stores internal commands and data while it is processing them are called ____________ .
> Computers use the ___________ numbering system.
> Computers use _____________ for main system memory.
> By lifting the arm on the ________________ you can easily remove a PGA CPU.
> Use of the _________ technology enables a processor to protect certain sections of memory.
> All of the machine language commands that the CPU understands make up the CPU’s ______ .
> On modern versions of Windows, the best file system to choose is ______________ .
> ____________ enables you to set up hard drives, manage devices, test system performance, and much more.
> The __________ enables a tech to perform most of the maintenance, upgrade, and configuration aspects of Windows.
> You can use __________ in Windows 8.1 to access files and folders.
> The _________ utility in Mac OS X enables you to switch easily among applications, windows, and Spaces.
> Move the cursor to the top or bottom right corner of the screen in Windows 8 to access one of the tools called a ________ .
> Windows 8’s tile-based interface is called the Metro/Modern UI or __________ .
> You can access frequently used applications in Mac OS X by clicking their icons on the ________ .
> Computers work through three basic stages, what’s called the ___________ .
> You can access the ___________ tool from the permanent Apple menu to administer a Mac.
> The term _________ refers to the software parts of the operating system with which you can interact.
> Instead of using a FAT, NTFS uses a _________ with a backup copy placed in the middle of the disk for better security.
> Once you have determined the problem with the machine and come up with probable causes, you should __________ .
> A customer complains that he can hear music coming from his computer speakers, even though the computer is not playing any music. This is most likely caused by ______________ .
> To begin troubleshooting a computer problem, start by talking to the customer and allowing the customer to explain the problem fully. Actively listen; then ask follow-up questions. This process is called ______________ .
> A magnetic field interfering with electronics is _______________ .
> You should avoid learning _________to other folks’ computers so you don’t get blamed if something happens to those computers.
> Accomplished computer techs should treat anything said to them as a personal confidence, not to be repeated to coworkers or bosses. A tech brings _________ to the job.
> An effective use of ________________ means clearly stating a problem without accusing the user of creating that problem.
> A few screwdrivers and an antistatic wrist strap should be in your__________.
> Once you have successfully repaired the machine, it is important to _________ with the user that everything is working correctly.
> Always place an expansion card or other computer part into a ___________ when it’s not in use to protect against electrostatic discharge.
> If a file is not stored in contiguous clusters, you can improve hard drive performance by using a tool to __________ the drive.
> A grouping of computers that enables people to share resources is called a(n) __________________.
> Typically, techs who attain CompTIA A+ certification then pursue __________________ to add to their computer credentials.
> You can find the latest information about the CompTIA A+ certification exams here: __________________.
> Persons desiring to work in Windows-based networking should pursue __________________ certification after completing their CompTIA certifications.
> You can use a __________________ when you schedule your exam to save some money.
> The __________________ company administers the CompTIA A+ certification exams.
> A term for a person who builds and maintains computers is __________________.
> A(n) __________________ gives clients and employers a level of confidence that you can do what you say you can do.
> You become CompTIA A+ certified by passing the __________________ and CompTIA A+ 220-902 exams.
> 1. What is the default file system in Windows? A. exFAT B. ext4 C. HFS+ D. NTFS 2. What is the default file system in Mac OS X? A. exFAT B. ext4 C. HFS+ D. NTFS 3. What is the default file system in most current Linux distros? A. exFAT B. ext4 C. HFS+
> 1. Jane replaced two 5400-RPM drives with a pair of 10,000-RPM drives, but now her system crashes under heavy use. What can she do to address this problem? A. Install drive bay fans to cool the new drives. B. Enable AHCI in the CMOS setup utility. C. Ena
> 1. Which of the following ATX12V features was introduced as part of the EPS12V standard? A. The P4 motherboard power connector B. Voltage rails C. The 6-pin AUX connector D. Soft power 2. Which kind of fire extinguisher should you use for computer equip
> 1. Which of the following are part of the ATX form factor? A. Mini-ITX B. macroATX C. microATX D. picoATX 2. Which of the following form factors dominates the PC market? A. AT B. ATX C. Mini-ITX D. Pico-ITX 3. Which of the following slots features seri
> 1. A user calls first thing Monday morning saying she has an error message at boot-up that says her case was opened. She’s looked at the computer, but it seems normal. What does this tell you about her computer? A. Her computer has TPM enabled in the CMO
> 1. What device enables a PC to retrieve a specific row of data from system memory and place it on the external data bus? A. Advanced micro device B. Arithmetic logic unit C. Floating point processor D. Memory controller chip 2. Which of the following st
> 1. What is the standard main screen/user interface used in all versions of Windows? A. Control Panel B. Dock C. Taskbar D. Desktop 2. How do you open an application in Windows? A. Left-click its icon. B. Right-click its icon. C. Left double-click its ic
> 1. While troubleshooting a fairly routine printing problem, the customer explains in great detail precisely what he was trying to do, what happened when he tried to print, and what he had attempted as a fix for the problem. At what point should you inter
> 1. Which of the following certifications is the de facto requirement for entrance into the PC industry? A. Certified Cisco Network Associate B. CompTIA A+ C. CompTIA Network+ D. Microsoft Certified Solutions Expert 2. John loves the Internet and wants a
> A _____________ requires exactly two volumes and is extremely fault tolerant.
> The MBR checks the partition table to find the __________ or bootable partition.
> Using the data in Exercise 4, test the hypothesis that the mean number of page views from the two websites is the same. You may assume that the number of page views from each website follows a Normal distribution. a) Calculate the P-value of the statist
> Using the data in Exercise 3, test the hypothesis that the mean age of houses in the two neighborhoods is the same. You may assume that the ages of houses in each neighborhood follow a Normal distribution. a) Calculate the P-value of the statistic knowi
> For the data in Exercise 2, we want to test the null hypothesis that the mean number of page visits is the same for the two websites. Assume that the data come from a population that is Normally distributed. a) Using the values you found in Exercise 2,
> For the data in Exercise 1, we want to test the null hypothesis that the mean age of houses in the two neighborhoods is the same. Assume that the data come from a population that is Normally distributed. a) Using the values you found in Exercise 1, find
> Not happy with the previous results, the analyst in Exercise 2 takes a much larger random sample of customers from each website and records their page views. Here are the data: a) Find the estimated mean difference in page visits between the two websit
> The developer in Exercise 1 hires an assistant to collect a random sample of houses from each neighborhood and finds that the summary statistics for the two neighborhoods look as follows: a) Find the estimated mean age difference between the two neighb
> A market analyst wants to know if the new website he designed is showing increased page views per visit. A customer is randomly sent to one of two different websites, offering the same products, but with different designs. Here are the page views from fi
> Using the summary statistics in Exercise 4, and assuming that the data come from a distribution that is Normally distributed, a) Find a 95% confidence interval for the mean difference in page views from the two websites. b) Why is the confidence interv
> Using the summary statistics in Exercise 3, and assuming that the data come from a distribution that is Normally distributed, a) Find a 95% confidence interval for the mean difference in ages of houses in the two neighborhoods using the df given in Exer
> Using the data in Exercise 2, and assuming that the data come from a distribution that is Normally distributed, a) Find a 95% confidence interval for the mean difference in page views from the two websites. b) Is 0 within the confidence interval? c) W
> Here are data from a small bookstore. The regression line is: The assumptions and conditions for regression are met, and from technology we learn that a) Find the predicted Sales on a day with 12 employees working. b) Find a 95% confidence interval
> A developer wants to know if the houses in two different neighborhoods were built at roughly the same time. She takes a random sample of six houses from each neighborhood and finds their ages from local records. The table shows the data for each sample (
> Suppose that you are testing the hypotheses H0: m = 16 vs. HA: m 6 16. A sample of size 25 results in a sample mean of 16.5 and a standard deviation of 2.0. a) What is the standard error of the mean? b) What is the critical value of t* for a 90% confid
> Suppose that you are testing the hypotheses H0: p = 0.40 vs. HA: p 7 0.40. A sample of size 200 results in a sample proportion of 0.55. a) Construct a 90% confidence interval for p. b) Based on the confidence interval, at a = 0.05 can you reject H0? Ex
> Suppose that you are testing the hypotheses H0: p = 0.20 vs. HA: p 0.20. A sample of size 250 results in a sample proportion of 0.25. a) Construct a 95% confidence interval for p. b) Based on the confidence interval, at a = 0.05 can you reject H0? Ex
> For each of the following situations, find the critical value for z or t. a) H0: m = 105 vs. HA: m 105 at a = 0.05; n = 61. b) H0: p = 0.05 vs. HA: p 7 0.05 at a = 0.05. c) H0: p = 0.6 vs. HA: p 0.6 at a = 0.01. d) H0: p = 0.5 vs. HA: p 6 0.5 at
> For each of the following situations, find the critical value(s) for z or t. a) H0: p = 0.5 vs. HA: p 0.5 at a = 0.05. b) H0: p = 0.4 vs. HA: p 7 0.4 at a = 0.05. c) H0: m = 10 vs. HA: m 10 at a = 0.05; n = 36. d) H0: p = 0.5 vs. HA: p 7 0.5 at a
> Which of the following statements are true? If false, explain briefly. a) It is better to use an alpha level of 0.05 than an alpha level of 0.01. b) If we use an alpha level of 0.01, then a P-value of 0.001 is statistically significant. c) If we use a
> Which of the following statements are true? If false, explain briefly. a) Using an alpha level of 0.05, a P-value of 0.04 results in rejecting the null hypothesis. b) The alpha level depends on the sample size. c) With an alpha level of 0.01, a P-valu
> For each situation below identify the population and the sample and explain what p and p represent and what the value of pn is. Would you trust a confidence interval for the true proportion based on these data? Explain briefly why or why not. a) A marke
> An investment website can tell what devices are used to access the site. The site managers wonder whether they should enhance the facilities for trading via “smartphones” so they want to estimate the proportion of users who access the site that way (even
> Here’s a scatterplot of the % of income spent on food versus household income for respondents to the Cornell National Social Survey: For each of the regression assumptions, state whether it is satisfied, not satisfied, or canâ&#
> In preparing a report on the economy, we need to estimate the percentage of businesses that plan to hire additional employees in the next 60 days. a) How many randomly selected employers must we contact in order to create an estimate in which we are 98%
> Which of the following are true? If false, explain briefly. a) If the null hypothesis is true, you’ll get a high P-value. b) If the null hypothesis is true, a P-value of 0.01 will occur about 1% of the time. c) A P-value of 0.90 means that the null hy
> It’s believed that as many as 25% of adults over age 50 never graduated from high school. We wish to see if this percentage is the same among the 25 to 30 age group. a) How many of this younger age group must we survey in order to estimate the proportio
> A business statistics class conducted a student survey in which 299 students were randomly selected and asked a variety of questions. One of the questions asked “How many friends do you have on Facebook?” To find a con
> The Framingham Heart Study recorded the cholesterol levels of more than 1400 participants in Framingham, MA (Data in Framingham). To find a bootstrap confidence interval for the mean cholesterol, a student took 1000 bootstrap samples, calculated the mean
> For the confidence intervals of Exercise 14, a histogram of the data looks like this: Check the assumptions and conditions for your inference. Exercise 14: For the purchase amounts in Exercise 8: a) Construct a 90% confidence interval for the mean pu
> For the confidence intervals of Exercise 13, a histogram of the data looks like this: Check the assumptions and conditions for your inference. Exercise 13: For the ages in Exercise 7: a) Construct a 95% confidence interval for the mean age of all cus
> A marketing analyst at an Internet book store is testing a new web design which she hopes will increase sales. She wants to randomly send n customers to the new site. She’s hoping for an increase of 10% in sales from the new site. She calculates a power
> Most car engines need at least 87 octane to avoid “knocking” or “pinging,” terms used to describe the preignition that can happen when a fuel’s octane is too low. An engineer is designing an experiment to raise the octane of an ethanol-based fuel. From p
> For each of the following situations, state whether a Type I, a Type II, or neither error has been made. a) A test of H0: m = 25 vs. HA: m 7 25 rejects the null hypothesis. Later it is discovered that m = 24.9. b) A test of H0: p = 0.8 vs. HA: p 6 0.8
> For the data from Exercise 1, which of the following conditions can you check from the scatterplot? Are satisfied? a) Linearity b) Independence c) Equal Spread d) Normal Population Exercise 1: A website that rents movies online recorded the age and the
> For each of the following situations, state whether a Type I, a Type II, or neither error has been made. Explain briefly. a) A bank wants to know if the enrollment on their website is above 30% based on a small sample of customers. They test H0: p = 0.3
> Suppose that you are testing the hypotheses H0: m = 80 vs. HA: m 80. A sample of size 61 results in a sample mean of 75 and a standard deviation of 1.5. a) What is the standard error of the mean? b) What is the critical value of t* for a 95% confiden
> Which of the following are true? If false, explain briefly. a) A P-value of 0.01 means that the null hypothesis is false. b) A P-value of 0.01 means that the null hypothesis has a 0.01 chance of being true. c) A P-value of 0.01 is evidence against the
> Instead of advertising the percentage of customers who improve by at least 10 points, a manager suggests testing whether the mean score improves at all. For each customer they record the difference in score before and after taking the course (After - Bef
> According to the 2010 Census, 11.4% of all housing units in the United States were vacant. A county supervisor wonders if her county is different from this. She randomly selects 850 housing units in her county and finds that 129 of the housing units are
> According to the 2010 Census, 16% of the people in the United States are of Hispanic or Latino origin. One county supervisor believes her county has a different proportion of Hispanic people than the nation as a whole. She looks at their most recent surv
> A test preparation company claims that more than 50% of the students who take their GRE prep course improve their scores by at least 10 points. a) Is the alternative to the null hypothesis more naturally one-sided or two-sided? Explain. b) A test run w
> Better than aspirin again? Referring to the study of Exercise 1: a) Is the alternative to the null hypothesis more naturally one-sided or two-sided? Explain. b) The P-value from a clinical trial testing the hypothesis is 0.0028. What do you conclude?
> As in Exercise 3, for each of the following situations, define the parameter and write the null and alternative hypotheses in terms of parameter values. a) Seat-belt compliance in Massachusetts was 65% in 2008. The state wants to know if it has changed.
> For each of the following situations, define the parameter (proportion or mean) and write the null and alternative hypotheses in terms of parameter values. Example: We want to know if the proportion of up days in the stock market is 50%. Answer: Let p =
> A soap manufacturer tested a standard bar of soap to see how long it would last. A test subject showered with the soap each day for 15 days and recorded the Weight (in grams) of the soap after the shower. The resulting regression computer output looks, i
> A friend of yours claims to be psychic. You are skeptical. To test this you take a stack of 100 playing cards and have your friend try to identify the suit (hearts, diamonds, clubs, or spades), without looking, of course! State the null hypothesis for yo
