Oth Glass

Computer Science

Time: 1.45 Hours


UR (4) questions: (@> roblem?

(i) How do we use gue unknown information through appropriate

2 Write short answers to any FO sses to define a Pp

> We try to guess the guesses. These guesses may (ii) On what thing does th depend upon? | ds upon the problem,

EXE The selection of a strategy depen | ybe more suitable to

is quite important that one strategy ma sl than the other one. Very specifically, the

implement a solution selection of the strategy depends upon the nature of a problam, (iii) Whatis decision making? ESS To determine whether a statement is true or false, and taking appropriate steps accordinaly, is called decision making, (iv) Write advantages of flowchart.

EX Following are the advantages of flowchart: 4. Easy to draw.

2. Easy to understand problem solving. 3. Easy to identify errors (if any). 4. Easy to observe flow from one step to the other.

(v) Define validation.

EX Validation means to test whether the solution is correc or not. For example, if you are asked to give a solution fo calculating compound interest, then validation means to know: whether it is-finding the correct compound interest or not. If é solution is verified, then it is validated with the help of test date as discussed in previous section. (vi) What is non-volatile/secondary memory?

: A device which can hold data even if it is not connectet 0 any power source, is called Non-Volatile Memory. The typica

be bases upon our past experiences, e selection of a Strategy

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examples for Non-Volatile Memory Ale hard diives. thea i |

and memory cards Installed in cell phones. bven i tee fee

our PC, the data In your hard drive or flesh diive iB fa wn olf wre a‘ titaet,

3. Write short answers to any FOUR (4) Quesllons: (14)

Dofine Booloan proposition. Give two examples,


A proposition is a sentence thal Gan elther be true or false. For example, the following sentences are propositions: 1. “Someone from our school can join Pakistan! Cricket


2. “| will get A+ grade in board exam”. (ii) Describe associative law of Boolean algebra,

EXE This law is for several variables, According to this law, there is no change in results if a grouping of expressions 16 changed. This law is quite same in cave of AND and OF

operators. (A+B) +C =A+(B+C)

(a) (b) (A.B). C#A. (B.C) (iii) Differentiate between server and client. ce and a client gets that service.

[EG A server provides a servi (iv) Define mesh topology. evices with each other

EX Mesh topology connects .all d through a direct link, As compared to ring topology, data may reach its destination quickly. | |

(v) | What is client-server overuse?

EXE installing more copies of, the software than you have licenses for, is known as client-server overuse. (vi) What are the trade secrets?

rets that are playing an

EN Trade secrets are usually the sec important role for the success of a company. They have a lot of

value and usefulness for the company. 4. _ Write short answers to any FOUR (4) (i) Define encryption. |

[XE Encryption is the proces way that only authorised person can

questions: _ (8)

5 of encoding data in such a read it.

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characteristics of agood password.

(ii) Write

ES A good password:

1. is at least eight characters long.

2. doesn't contain your user name, real name, kid's Name or company name. |

3 doesn't contain a complete word.

4 is significantly different from previous passwords.

5 contains uppercase letters, lowercase letters, numbers,

and symbols. (iii) | Whatare singular tags? EE some tags do not have closing tags and they are calleq

; or empty tags. They are simply written as ae example, <br> for line break, <hr> to insert a

(iv) aoa mals types of list in HTML?

E> There are four types of list in HTML.

(v) Define ordered list. | 3

EGE An ordered list keeps each list item with an order

the order, the meaning of the whole list number. If you change your teacher makes a list of

example, if ca hor beac to coil then definitely order will matter. (vi) Define colspan.. . EX To make a cell span more than one columns, colspan attribute is used. ) (Part-ll)

NOTE: Attempt any Two (2) questions. , 55

Q.5. Describe flowchart symbols through table. Ansa Flowchart Symbols: |

Flowcharts explain a process clearl through symbols and text. They use special shapes to-represent different types of actions or steps in a process. Lines and arrows show the flow of the steps. Table shows some of the most widely used symbols in flowcharts:

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a nen

_ Name | _ Description


: “low line ee | steps Ina flowchart.

“Tit indicates start and end of al = © Terminal | fowchart, | it represents operations to chan > ge Process | values.

it shows a conditional operation that determines which one of the

Decision | two paths to take. The operation is commonly a yes/no question or a true/false test.


a aeaeed

It indicates the input of data from Input/Output user or displaying results to user.

if a flowchart doesn't fit on a page, Connector

then we use connector to connect narts of a flowchart on different pages. Q.6. Convert (110101111), to hexadecimal. _ (8) EGE convert (110101111), to hexadecimal: The groups in this binary number are given

each group has maximum four binary digits.

110101111 | | The left most group in blue colour has only 1 binary digit

and by adding Os, we get: . 000110101117 | * | We replace each group with the respective hexadecimal

and get:

below where

1AF So, (110101111), = (1AF),

ss yanmar ata Q.7. Analyze the personal privacy and security concerns that arise with any use of computational systems. (8)

EGE> with the advent of Internet, our computers are no longer

stand-alone devices. In fact, now they are connected to millions

of other computers in the world. Due to this connectivity, many

rites concems also arise. Primarily, we want to secure our ala according to the.following three aspects:

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Se onfidentiality: | ey a : a means-that we want to keep our data as conf We do not want to share it with unintended persons. 2. te ena that we want to keep the data correct. Fis example, we do not want that the website of our bank Shows less account balance than it actually is. | 3, Availability: Peter eee ba

It means that we want to have access to the data whe we want. If data is not available when needed, then in Some cases it becomes useless. | sj itis as |

All these aspects are important during the Processing storage and transmission of data in a computerized system. ~'

Computation is a general term for-any type of informatioy processing that can be represented mathematically. Fo, example, your grade in 9th class will be computed according to your marks in every subject. | inn Beeaeeee comp eertyone’s life, there is ‘stunning growth of, usage of Pailin REM eee pehind raising concems


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