Computer Science: CUET Mock Test - 8 - CUET MCQ

The correct matching pairs are

Statement I is correct because it follows the LIFO(Last in First Out). It means you can delete that element which comes first. Statement II is incorrect because elements can be deleted only from the top in Stack data structure.

ADD is not a keyword in SQL.

The union operator requires that both relations are union-compatible. This means that they are required to have the same set of attributes.

Metadata is the data about the data. Anything that describes the database—as opposed to being the contents of the database—is metadata. Metadata stored in the MySQL in the MySQL database mysql

A DDL performs the following functions :

1. It identifies the type of data division such as data item, segment, record and database file.
2. It gives a unique name to each data item type, record type, file type and data base.
3. It specifies the proper data type.
4. It defines the size of the data item.
5. It may define the range of values that a data item may use.
6. It may specify privacy locks for preventing unauthorized data entry.

Correct Prefix notation for the (a+b)*(c-d) is *+ab-cd(a+b)*(c+d) = (+ab)*(-cd) = *+ab-cd (Statement I is Incorrect). Postfix notation for the (a+b)*(c-d) is *+ab-cd(a+b)*(c-d) = (ab+)*(cd-) = ab+cd -* (Statement II is Correct).

The 'is empty ( )' function can be also be written by using '? :'.

A stack pointer is a small register that stores the address of the last program request in a stack. A stack is a specialized buffer which stores data from the top down. Both stack and stack pointers reside in the memory.

A cookie stores information about the user's web activity.
They are small files often including unique identifiers that web servers send to browsers. They can be sent back to the server each time your browser requests a new page. It helps browsers remember your preferences and habits online.

With random hashing, the probe sequence is generated by the output of a pseudorandom number generator seeded by the key (possibly together with another seed component that is the same for every key, but is different for different tables)

These are the built-in exceptions in Python:

• 'ValueError' is raised when an invalid argument is passed to a function.
• 'TypeError' is raised when an operation or function is applied to an object of inappropriate type.
• 'IndexError' is raised when an index is out of range.
• 'KeyError' is raised when a dictionary key is not found.

Information includes the processed data by planning, controlling and analysing.

This communication protocol prevents a fast sender from flooding a slow receiver with data, by regulating the flow of data on communication lines.

You can treat a tuple as a kind of record, where the index of an element in a tuple is its name within the equivalent record, so (10, 25) is {0 : 10, 1 : 25}. I believe 'Standard ML' and related languages use records as the basic unit of type conjunction (algebraic data types provide type dis-junction) and treat tuples as a kind of record in this way.

Database Management Systems (DBMS) are software systems used to store, retrieve, and run queries on data. A DBMS serves as an interface between an end-user and a database, allowing users to create, read, update, and delete data in the database.

Data Definition Language(DDL) is a subset of SQL and a part of DBMS(Database Management System). DDL consist of Commands to commands like CREATE, ALTER, TRUNCATE and DROP. These commands are used to create or modify the tables in SQL.

Transmission media is basically divided into two categories:

• Broadcast Networks
• Point-to-Point Networks

Spyware, in context of computer software, is software that aims to gather information about a person without his/her knowledge, and that may send such information to another entity.
Spyware is mostly used for stealing information, storing internet users' movements on the web, and serving up pop-up ads to the internet users. Whenever a spyware is used for malicious purposes, its presence is typically hidden from the user and can be difficult to detect. Some spyware, such as keyloggers, may be installed by the owner of a shared, corporate, or public computer intentionally in order to monitor users.

Protocol is a set of rules and regulations. It defines the rules and regulations for communication over the network.

Concept:
Each computer server hosting a website or web resource is given a name against its IP address. These names are called domain names or hostnames.

• The Internet is a vast ocean where information is available in the form of millions of websites. Each website is stored on a server that is connected to the internet, which means each server has an IP address.
• Every device connected to the internet has an IP address. To access a website, we need to enter its IP address on our web browser.
• But it is very difficult to remember the IP addresses of different websites as they are in terms of numbers or strings.
• Conversion of the domain name of each web server to its corresponding IP address is called domain name resolution.

Concept:
10 Mbps to 1 Gbps of data transport are supported by Ethernet cards (1000 Mbps). A MAC address, which is present on every NIC, aids in uniquely identifying each computer on the network.

• A network adapter used to set up a wired network is an Ethernet card, sometimes referred to as a Network interface card. It serves as the network's and computer's interface.
• A computer's motherboard has a circuit board attached to it. The computer's NIC links it to the network through the ethernet wire.
• An ethernet connection is the most often used network connection for personal computers. Actually, Ethernet is a communication protocol and hardware description standard for computer network architectures.
• With its wide applications, there are various types of network interface cards emerging in the market like PCIe cards and server network cards.
• A network interface card connects the clients, servers, and peripherals to the network through a port.
• NIC allows a computer to connect to a computer network through Ethernet or WiFi. Ethernet: wired connection. WiFi: wireless connection.

Stack works in a LIFO manner. That is last in first out, the element which inserted last should come out first.
X statement considers the same real-life application as a stack.10 plates were placed over another and made a tower. This is the same as a stack structure. when we remove a plate from the top, the last inserted plate will come out. So, it's an application of stack.
Queue works on FIFO pattern ( first in first out), The element inserted first should come out first. 
Statement Y is an example of a queue, because 10 customers waiting for their turn in an interactive voice response system, in that the customer who connected to the line first will be served first. That's a FIFO property, So, Statement Y is an example of the queue.
A similar example of Stack-

• Tower of Hanoi, Disc kept in a cylindrical box 
• Queue- people waiting to book a ticket.

The correct answer is option A.

Concept:
The given python code is,
tell() method:
This function returns an integer that specifies the current position of the file object in the file. The position so specified is the byte position from the beginning of the file till the current position of the file object.
The syntax of using tell() is:
file_object.tell()
The given code is,
fp = open("sample2.txt", "w")
print(fp.tell())
fp.write('12345678')
print(fp.tell())
fp.close()

Explanation:
The given sample2.txt opens the file in write mode. If the file already exists, all the contents will be overwritten. If the file doesn’t exist, then a new file will be created.
Here is the file newly created and write the contents. And we will notice the position of the handle before writing and after writing to the Sample2.txt file.
the position of the handle before writing=0
after writing to the Sample2.txt file = 8
Hence the correct answer is 
0
8

Concept:

A network interface controller (NIC) is given a media access control address (MAC address), which it can use as a network address in communications inside a network segment.

• To send Ethernet frames to a computer, utilize the MAC address. The operating system and the NIC exchange data through the NIC driver software.
• Although each MAC address is exclusive to the network card that is placed on a device, because there are only so many device-identifying bits available, manufacturers occasionally reuse them.
• NIC, or network interface card, is a shortened form. Network adapter and Ethernet card are other names for NIC. The device that enables a computer to connect to a network, such as a home network, is an expansion card or hardware interface.

The de queue is a combination of both queue and stack,  where we can push and pop from both left and right sides. So, it can be used as both stack and queue, 
In stack, we use to insert in the front, and in the queue, we used to insert from the back. So, both work we can do on de queue, That's why it's called as Double Ended queue.
dequeue allows you to efficiently add or remove the item from Either end of the list. 
So, the Assertion statement is correct. 
Now, the reason is also true and correctly explains the assertion. In the de queue, we can insert and delete from both the ends that's why it can support both stack and queue.
de queue is implemented as a double-linked list in the system and we can insert and delete from both ends.

So, option C turns out to be the correct answer as Reason correctly explains the Assertion.  

The correct answer is option A.

Concept:
When an error occurs, the Python interpreter creates an object called the exception object. This object contains information about the error like its type, file name, and position in the program where the error has occurred.
The object is handed over to the runtime system so that it can find an appropriate code to handle this particular exception. This process of creating an exception object and handing it over to the runtime system is called throwing an exception. 

Hence the correct answer is throwing an exception.

• The DATE data type is used for storing a date in database tables. The supported dates range from 1000-01-01 to 9999-12-31.
• The default format of this data type is the 4-digit year, followed by 2-digit month and 2-digit day. The 3 values are separated by hyphens (-).

Type Error usually comes when a user tries to do an operation between different types of data types. 

Here in print(525+'525')- 
525 is an integer data type, and '525' is a string data type, So, Python does not support the use of + operator between two different data types. So, it will throw a Type Error. 

CORRECTION OF THE CODE - 
This code can be corrected by- print(525+525) - using both integer data type , Output- 1050
OR 
print('525'+'525') - using both string data type , Output- '525525' ( This is called as string concatenation ) 

So, option c will be the answer. 

• The first statement imports the Pickle package of Python. This package is used to save an object structure along with the current data. This package is useful for retrieving a previous data state at any time. The statement does not contain any error.
• The second statement opens a binary file, data.dat in the “read in binary” mode using the open() function. The file handle is stored in the variable f. The open() function takes the file name and the mode of operation as parameters. Thus, this statement is correct.
• The load() function of the Pickle module is used to unpickling data from a binary file. The returned data then needs to be stored in a variable. In statement 3, the load() function is invoked using ‘pickles’, but the module which contains this function is called pickle. So, this statement is incorrect.
• A file must be closed after working on it. The close() function is used with the file handler variable for this.