Which is NOT a standard RAID level?

Which is NOT a standard RAID level?

• 7
• 2
• 0
• 5 

EXPLANATION

RAID 2, which is rarely used in practice, stripes data at the bit (rather than block) level, and uses a Hamming code for error correction. The disks are synchronized by the controller to spin at the same angular orientation (they reach index at the same time^{[clarification needed]}),
so it generally cannot service multiple requests simultaneously.^[16][17] However, depending with a high rate Hamming code, many spindles would operate in parallel to simultaneously transfer data so that "very high data transfer rates" are possible^[18] as for example in the DataVault where 32 data bits were transmitted simultaneously.
With all hard disk drives implementing internal error correction, the complexity of an external Hamming code offered little advantage over parity so RAID 2 has been rarely implemented; it is the only original level of RAID that is not currently used.

 

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Which of these logic constructs most efficiently (in terms of code conciseness and variable reuse) allows you to select and execute one code block out of 3 or more based on the value of a single variable?

Which of these logic constructs most efficiently (in terms of code conciseness and variable reuse) allows you to select and execute one code block out of 3 or more based on the value of a single variable?

• while
• for
• if
• switch

EXPLANATION

if statement

People make decisions on a daily basis. What should I have for lunch? What should I do this weekend? Every time you make a decision you base it on some criterion. For example, you might decide what to have for lunch based on your mood at the time, or whether you are on some kind of diet. After making this decision, you act on it. Thus decision-making is a two step process – first deciding what to do based on a criterion, and secondly taking an action.
Decision-making by a computer is based on the same two-step process. In Python, decisions are made with the if statement, also known as the selection statement. When processing an if statement, the computer first evaluates some criterion or condition. If it is met, the specified action is performed. Here is the syntax for the if statement:

if condition:
    if_body

When it reaches an if statement, the computer only executes the body of the statement only if the condition is true. Here is an example in Python, with a corresponding flowchart:

if age < 18:
    print("Cannot vote")

 

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What does the acronym ZIF stand for?

What does the acronym ZIF stand for?

• Zero Incident Frequency
• Zero Interesting Facts
• Zero Insertion Force
• Zero Intermediate Frequency 

EXPLANATION

ZIF. Stands for "Zero Insertion Force." ZIF is a type of CPU socket on a computer motherboard that allows for the simple replacement or upgrade of the processor. Processors that use a ZIF socket can easily be removed by pulling a small release lever next to the processor and lifting it out.

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What are the components of the CIA triad of information security?

What are the components of the CIA triad of information security?

• Threat, vulnerablity, and exploit
• Access control, whitelist, and blacklist
• Confidentiality, integrity, and availability
• Authentication, authorization, and accounting 

EXPLANATION

In 1998, Donn Parker proposed an alternative model for the classic CIA triad that he called the six atomic elements of information. The elements are confidentiality, possession, integrity, authenticity, availability, and utility.

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Which of the following malware threats propagates without action by the distributor or the victim?

Which of the following malware threats propagates without action by the distributor or the victim?

• Rootkit
• Virus
• Worm
• Trojan 

EXPLANATION

Computer worms are similar to viruses in that they replicate functional copies of themselves and can cause the same type of damage. In contrast to viruses, which require the spreading of an infected host file, worms are standalone software and do not require a host program or human help to propagate.
To spread, worms either exploit a vulnerability on the target system or use some kind of social engineering to trick users into executing them. A worm enters a computer through a vulnerability in the system and takes advantage of file-transport or information-transport features on the system, allowing it to travel unaided. More advanced worms leverage encryption, wipers, and ransomware technologies to harm their targets.

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