List of top Questions asked in CBSE CLASS XII

‘Swabhaav’ is a big NGO working in the field of Psychological Treatment and Counselling, having its Head Office in Nagpur. It is planning to set up a center in Vijayawada. The Vijayawada Center will have four blocks – ADMIN, PSYCHIATRY, PSYCHOLOGY, and ICU. You, as a Network Expert, need to suggest the best network-related solutions for them to resolve the issues/problems mentioned in questions (i) to (v), keeping the following parameters in mind: 

Suman has created a table named WORKER with a set of records to maintain the data of the construction sites, which consists of WID, WNAME, WAGE, HOURS, TYPE, and SITEID. After creating the table, she entered data in it, which is as follows : 

A CSV file "P_record.csv" contains the records of patients in a hospital. Each record of the file contains the following data:
- Name of a patient
- Disease
- Number of days patient is admitted
- Amount

For example, a sample record of the file may be:
["Gunjan", "Jaundice", 4, 15000]

Write the following Python functions to perform the specified operations on this file:

(i) Write a function read_data() which reads all the data from the file and displays the details of all the 'Cancer' patients.

(ii) Write a function count_rec() which counts and returns the number of records in the file.
Write the following user-defined functions in Python:

(i) push_trail(N, myStack): Here N and myStack are lists, and myStack represents a stack.
The function should push the last 5 elements from the list N onto the stack myStack.
Assume that N contains at least 5 elements.

(ii) pop_one(myStack): The function should pop an element from the stack myStack, and return this element.
If the stack is empty, then the function should display the message 'Stack Underflow', and return None.

(iii) display_all(myStack): The function should display all the elements of the stack myStack, without deleting them.
If the stack is empty, the function should display the message 'Empty Stack'.
Predict the output of the following code:

def ExamOn(mystr):
    newstr = ""
    count = 0
    for i in mystr:
        if count % 2 != 0:
            newstr = newstr + str(count - 1)
        else:
            newstr = newstr + i.lower()
        count += 1
    newstr = newstr + mystr[:2]
    print("The new string is:", newstr)

ExamOn("GenX")
A stack, named ClrStack, contains records of some colors. Each record is represented as a tuple containing four elements — ColorName, RED, GREEN, BLUE. ColorName is a string, and RED, GREEN, BLUE are integers. For example, a record in the stack may be ('Yellow', 237, 250, 68).

Write the following user-defined functions in Python to perform the specified operations on ClrStack:

(i) push_Clr(ClrStack, new_Clr): This function takes the stack ClrStack and a new record new_Clr as arguments and pushes this new record onto the stack.

(ii) pop_Clr(ClrStack): This function pops the topmost record from the stack and returns it. If the stack is already empty, the function should display the message "Underflow".

(iii) isEmpty(ClrStack): This function checks whether the stack is empty. If the stack is empty, the function should return True, otherwise the function should return False.
Nisha is assigned the task of maintaining the staff data of an organization. She has to store the details of the staff in the SQL table named EMPLOYEES with attributes as EMPNO, NAME, DEPARTMENT, BASICSAL to store Employee’s Identification Number, Name, Department, and Basic Salary respectively. There can be two or more Employees with the same name in the organization.
(i)
(a) Help Nisha to identify the attribute which should be designated as the PRIMARY KEY. Justify your answer.
OR
(b) Help Nisha to identify the constraint which should be applied to the attribute NAME such that the Employees’ Names cannot be left empty or NULL while entering the records but can have duplicate values.
(ii)
(a) Write the SQL command to change the size of the attribute BASICSAL in the table EMPLOYEES to allow the maximum value of 99999.99 to be stored in it.
OR
(b) Write the SQL command to delete the table EMPLOYEES.
Write a Python function that displays all the words starting and ending with a vowel from a text file "Report.txt".
The consecutive words should be separated by a space in the output.
For example, if the file contains:
Once there was a wise man in a village.
He was an awesome story-teller.
He was able to keep people anchored while listening to him.
Then the output should be:
Once a a awesome able
Expand the term PPP. What is the use of PPP?
Write a Python function that displays all the lines containing the word 'vote' from a text file "Elections.txt".
For example, if the file contains:
In an election many people vote to choose their representative.
The candidate getting the maximum share of votes stands elected.
Normally, one person has to vote once.
The process of voting may vary with time and region.
Then the output should be:
In an election many people vote to choose their representative.
Normally, one person has to vote once.
Expand and explain the term URL.
The code given below accepts N as an integer argument and returns the sum of all integers from 1 to N. Observe the following code carefully and rewrite it after removing all syntax and logical errors. Underline all the corrections made.

def Sum(N):
    S = 0
    for I in range(1, N + 1):
        S = S + I
    return S

print(Sum(10))
What possible output from the given options is expected to be displayed when the following code is executed?
import random
Cards = ["Heart", "Spade", "Club", "Diamond"]
for i in range(2):
    print(Cards[random.randint(1, i+2)], end="#")
Consider the following dictionaries, D and D1:
D = { "Suman": 40, "Raj": 55, "Raman": 60 }
D1 = { "Aditi": 30, "Amit": 90, "Raj": 20 }

(Answer using built-in Python functions only)

(i)
(a) Write a statement to display/return the value corresponding to the key "Raj" in the dictionary D.

OR

(b) Write a statement to display the length of the dictionary D1.

(ii)
(a) Write a statement to append all the key-value pairs of the dictionary D to the dictionary D1.

OR

(b) Write a statement to delete the item with the given key "Amit" from the dictionary D1.
Assertion (A): We can retrieve records from more than one table in MYSQL.
Reason (R): Foreign key is used to establish a relationship between two tables.
What does the return statement do in a function? Explain with the help of an example.
Write one example of each of the following in Python:
(i) Syntax Error
(ii) Implicit Type Conversion
Which of the following options is the correct protocol used for phone calls over the internet?
Expand ARPANET.
Assertion (A): For a binary file opened using 'rb' mode,
the pickle.dump() method will display an error.
Reason (R): The pickle.dump() method is used to read from a binary file.
State True or False:
If table A has 6 rows and 3 columns,
and table B has 5 rows and 2 columns,
the Cartesian product of A and B will have 30 rows and 5 columns.
Which aggregate function in SQL displays the number of values in the specified column ignoring the NULL values?
Which of the following networking devices is used to regenerate and transmit the weakened signal ahead?
In MYSQL, which type of value should not be enclosed within quotation marks?
Which of the following built-in function/method returns a dictionary?