When a path goes from node A1 to node C2 in Fig. 1 and the passing nodes are counted as shown in Fig. 2, there are three shortest paths with the minimum number of passing nodes. How many shortest paths are there available to go from node A1 to node D4 via node C2?

• 6

• 9

• 12

• 20

The procedure decribed below is sequentially performed for two variables x and y,s tarting with step (1). When the procedute is completed, what is the resulting value of x?

[PROCEDURES]

1. Asign 2 to x and 3 to y.

2. Subtract 1 from the value of x and y, and assign the resulting value of to y.

3. Add the values of x and y, and assign the resulting value to x.

4. If the value of y is 1, complete the procedure, Otherwise, return to step (2)

• 4

• 5

• 7

• 8

Answer explanation

Starting with step (1), we have:

Step 1: x = 2, y = 3

Step 2: x = 2-1 = 1

y = 3-1 = 2

Step 3: x = 3

y = 2

---------

x = 5, y=2

Step 4: If the value of y is 1, complete the procedure, Otherwise, return to step (2)

Step 2: x = 5-1 = 4

y = 2-1 = 1

Step 3: x = 4

y = 1

---------

x = 5, y=1

x = 5, y = 1 (the procedure is completed as y equals 1)

Therefore, the resulting value of x is 5.

Wwhich of the following is an appropreiate description concerning a CPU?

• The cache memory that is integrated ino a CPU is used to virtually extend the capacity of the amin memory.

• A CPU is equipped with woth the arithmetic and logical function that serves as part of control functions.

• A CPU is categorized as a 16-bit, 32-bit, or 64-bit CPU depending on the data volume processed at a time, but the width in bits is not related to the performance.

• For CPUs that have the same architecture, the higher the clock frequency, the faster the response time.

Which of the following is an appropriate description concerning flash memory?

• It becomes read-only storage once data is written.

• No power supply is required to retain stored data.

• It is not used for digital cameras because of the difficulty of downsizing.

• Data is read or written using laser light.

Which of the following is an appropriate description about a device driver?

• Software for controlling and operating peripherals that are connected to a PC.

• Software that is started immediately after a PC is turned on, and enables basic input/output to the hard disk and the keyboard before OS starts.

• software to be embedded in a Web browser for displaying pages that contain video.

• software that integrates multiple files into one (1) file and restores the original files from the file.

When MTBF is 600 hours MTTR is 12 hours, what is the approximate availability?

• 0.02

• 0.20

• 0.88

• 0.98

Answer explanation

To calculate the approximate availability, we can use the following formula:

Availability = MTBF / (MTBF + MTTR)

where MTBF is the mean time between failures and MTTR is the mean time to repair.

Substituting the given values, we get:

Availability = 600 / (600 + 12)

Availability = 600 / 612

Availability = 0.98 or 98%

Therefore, the approximate availability is 98%.

Which of the following is an explanation of characteristics f a dual system?

• It provides two sets of systems that perform the same process by comparing the results. If one of the systems isolates the failed systems and continues the processing.

• The same two devices are used, so that the processing capability can be increased to double that os a simplex system.

• It provides a currently used system f performing online processing and also a backup system that is made on standby while performing batch processing. In the event of a failure in the currently used system, it switches to the backup system, starts the online processing on it, and continues the service.

• It connects multiple devices in series and configures them in such a way that the load of each function is distributed among them, so that processing capability is high. But if any of the devices fails, it become unable to provide the service.

What is the minimum amount (in Mbytes) of virtual memory that is required under the conditions below?

[Conditions]

1. Memory required for OS: 200 Mbytes

2. Memory required of applicants; An amount of 50 Mbytes is required for each application, and a total is calculated by multiplying it by the number of applications that run concurrently. Eight applications run concurrently.

3.Memory required for controlling main memory or other related functions: IN additions to 512 Mbytes of main memory, a minimum amount of 20 Mbytes is required.

4. Required virtual memory: The required amount is the sum of the above 1 through 3.

• 762

• 782

• 1,112

• 1,132

Answer explanation

To calculate the minimum amount of virtual memory required, we need to add up the memory required for the operating system, the running applications, and the controlling functions. Then, we need to subtract the physical memory available to determine the virtual memory needed. Here are the calculations:

1. Memory required for OS: 200 Mbytes

2. Memory required for running 8 applications: 8 x 50 Mbytes = 400 Mbytes

3. Memory required for controlling main memory: 20 Mbytes

4. Total memory required: 200 Mbytes + 400 Mbytes + 20 Mbytes + 512 Mbytes = 1132 Mbytes

If the system has 512 Mbytes of main memory, then the minimum amount of virtual memory required is:

Minimum Virtual Memory Required = Total Memory Required - Physical Memory Available

Minimum Virtual Memory Required = 1132 Mbytes - 512 Mbytes

Minimum Virtual Memory Required = 620 Mbytes

Therefore, the minimum amount of virtual memory required under the given conditions is approximately 620 Mbytes.

Which of the following explains the functions of an archiver, which is one (1) type of data management utility?

• It creates areas on hard disks for storing data and managing such stored data.

• It packs multiple files into a single file or restores them for data backup or distribution.

• It protects data through such functions as file protection to secure the data from unauthorized use or destruction, and copy protection to prevent illegal data copying.

• On a fragmented hard disk, it reorganizes files by placing them in consecutive blocks as much as possible.

Which of the following is an appropriate description concerning OSs used for PCs?

• Sincere the interface between an OS and application programs can be developed without regard to the type of OS

• An OS allocates the computer resources, such as the CPU, memory, and auxiliary storage device, to application programs.

• Since an OS has te function of automatically converting character set of a file, application programs can access the file without regard o the character set.

• THe source code of an OS is required to be disclosed so that application programs can be free various functions of the OS.