Revision

 Questions/Answers

Question 1: What do you mean by computer network? What is the purpose of creating network?

Answer    :A computer network is a group of two or more computers that are connected with each other to share a resource. Sharing of devices and resources is the purpose of computer network. You can share printers, fax machines, scanners, network connection, local devices and other resources.

Question 2: What advantages does fiber optics have over other media?

Answer    :One major advantage of fiber optics is that it is less susceptible to electrical interference . It also support higher bandwidth, meaning more data can be transferred and received. Signal degrading is also very minimal over long distances.

Question 3: Defines the terms:(i)Modem (ii)Guided media (iii)Network Transmission Media (iv)Twisted Pair

Answer     : Modem: Modem is a modulator and demodulator devices that converts data from analog to digital and digital to analog. The data signals generated by the sender computer is digital signals can not carried out by telephone line thus it can be converted to analog signal and then transmit through the communication channel at the receiver hand it again converted from analog to digital with the help of modem and received by receiver computer.

Guided media: Guided media is also known as Wired or Bound Transmission media. In guided media signals are confined to a specific path using wire or cable. These media are made up of external conductor(usually copper) bounded by jacket material. Some of commonly used media are co-axial cable, twisted pair cable and fibre optics cable. Each of them has its own characteristics like transmission speed, effect of noise, physical appearance, cost etc.

Network Transmission media: Network Transmission media is a path that carries the information or data from sender to receiver. An electrical signal is in the form of current where as an electromagnetic signal is series of electromagnetic energy pulses at various frequencies. It can be guided or unguided. Transmission media is also known as communication channel.

Twisted pair cable: Twisted pair cable is a type of cabling that is used for telephone communication.

• It has a pair of twisted conductor
• The twisting in twisted pair reduces interference.

Question 4: What is the role of Satellite Microwave? Give its advantage and disadvantages.

Answer : Satellite microwave transmission systems are similar to terrestrial microwave systems except that the signal travels from a ground station on earth to a satellite and back to another ground station on earth.

Advantages:

• Since the transmitting station can receive back its own transmission, so it can check whether information transmitted correctly or not.
• A single microwave relay station is visible from any point.

Disadvantages:

• Cost of making the satellite is very high.
• The transmission highly depends on weather conditions.

Question 5: What is Cyber Safety?

Answer: Cyber safety is a part of computer security which is applied to networks and corresponding computers so we can define 'Cyber Safety' as secure use of information and communication or safe and responsible use of information and communication technology.

Question 6: Define the following terms: i)virus  ii)trojans   iii)Spyware  iv)worms  v)Ransomware vi)Adware  vii)Botnets

Answers: Virus: Viruses attach themselves to clean files and infect other clean files. They can spread uncontrollably, damaging a system's core functionality and deleting or corrupting files. They usually appear as an .exe file.

Trojans: Trojans disguises itself as legitimate software or is included in legitimate software that has been tampered with.

Spyware: Spyware is also a malicious program that is designed to spy on you. It hides itself in the background and observe your activity online.

Worms: Worm also infect entire networks of devices by replicating itself, either local or across the internet, by using network interfaces.

Ransomware: This kind of malware can lock down your computer and threaten to copy your data or erase everything unless a ransom is paid to its owner.

Adware: Adware are advertising software which can undermine your security just to serve you ads. They appear as a pop-up also.

Botnets: Botnets are networks of infected computer that are made to work together under the control of an attacker.

Question 7: What is the difference between Antivirus and Antimalware?

Answer: 

Antivirus

• Protects against viruses.

• Signature-based detection

• Prevents malicious script from running

• Can only identify threats it's seen before.

Anti-malware

• Protects against malware.

• Heuristic-based detection

• Proactively detects and removes

suspicious activity

• Can identify threats it's never seen before.

Question 8: What is header and footer and where do we insert header and footer in the document?

Answer: Header and footer are areas where some text or graphics is usually printed at the top and bottom respectively on each page. A header is always printed inside top margin of the page and a footer is always printed inside the bottom margin of the page. Header and footer normally contains date, time, page number etc, author name etc.

Question 9: What is the purpose of page preview?

Answer: Before printing your document, you can see how your document will look after printing in the page preview option. Click on file menu and choose page preview option. A page preview toolbar appears. You can view one or more pages by reducing the size of the page. You can zoom in or Zoom out the page.

Question 10: What do you mean by track changes?

Answer:  In word processing, track changes is an editing command that is commonly used when you create an original document and make changes and want to keep track of the changes that are made to that original document.

Questions 11: What are spreadsheet? Give two examples of spreadsheet software?

Answer:  A spreadsheet is a software that has rows and columns arranged in a worksheet and this sheet is often used in business and financial applications for calculating and analyzing large amount of data. The two examples of Spreadsheet software are MS Excel, Lotus 1-2-3.

Question 12: What is the purpose of naming a range?

Answer: The named range can later be used in a formula e.g., you have entered numeric values in cell A1 to A5. Now you want to add the values of A1 to A5, so you can use the in-built function sum with value or with named range, like =SUM(A1:A5). If you name the range A1 to A5 as 'hello' then you use the formula like =SUM(hello).

Question 13: From the table given below, write the functions for the task given:

	A	B	C	D	E
1	Item name	Qty.	Price	Amount
2	Soap	5	25.75
3	Milk	7	50.75
4	Biscuit	10	20.00
5	Coffee	20	225.00
6	Tea	15	250.00
7	Brush	16	27.00
8	Pen	25	2300

1. To calculate the amount of each item in column D.
2. To find the average price in cell E1.
3. To find the maximum amount in cell E2.
4. To find the minimum quantity in cell E3.

Answer:

	A	B	C	D	E
1	Item name	Qty.	Price	Amount	=AVERAGE(C2:C8)
2	Soap	5	25.75	=C2*B2	=MAX(D2:D8)
3	Milk	7	50.75	=C3*B3	=MIN(B2:B8)
4	Biscuit	10	20.00	=C4*B4
5	Coffee	20	225.00	=C5*B5
6	Tea	15	250.00	=C6*B6
7	Brush	16	27.00	=C7*B7
8	Pen	25	2300	=C8*B8

Question 14: From the table given below, find the total marks all the students and also find wheather the student are pass or fail using if() function.

	A	B	C	D	E	F
1	Name	English	Science	Maths	Total	Pass/fail
2	Amit	57	30	90
3	Anil	98	90	80
4	Rajesh	85	55	72
5	Raghav	78	65	86
6	Santatan	92	98	95
7	Surya	27	20	20

Answer:

	A	B	C	D	E	F
1	Name	English	Science	Maths	Total	Pass/fail
2	Amit	57	30	90	=Sum(B2:D2)	=IF(E2<250;”FAIL”;”PASS”)
3	Anil	98	90	80	=Sum(B3:D3)	=IF(E3<250;”FAIL”;”PASS”)
4	Rajesh	85	55	72	=Sum(B4:D4)	=IF(E4<250;”FAIL”;”PASS”)
5	Raghav	78	65	86	=Sum(B5:D5)	=IF(E5<250;”FAIL”;”PASS”)
6	Santatan	92	98	95	=Sum(B6:D6)	=IF(E6<250;”FAIL”;”PASS”)
7	Surya	27	20	20	=Sum(B7:D7)	=IF(E7<250;”FAIL”;”PASS”)