List of top Questions asked in CBSE CLASS XII

Write the output of the following code:

import pandas as pd
s1 = pd.Series ([1, 2, 3], index = ['a','b','c'])
s2 = pd.Series ([4, 5, 6], index = ['b','c','d'])
print (s1 + S2)

Mandeep received an email stating he won a lottery though he had never participated in any such event. He was asked to provide bank details to process the amount. Mandeep provided the required details but within next few minutes ₹ One lakh was debited from his account.

Answer the following questions based on the given case study:

(i) Mandeep is the victim of which type of cybercrime?

(ii) Other than email, mention any two common methods through which this type of cybercrime is being committed these days.

(iii) Name one law that safeguards the rights of Internet users in India.

Write a Python program to create and display a Pandas Series as shown below:

The index labels are the names of the months – July, Aug, Sept, Oct.

The corresponding scalar values are the number of days in these respective months – 31, 31, 30, 31.

Niharika wants to create a Pandas Series using a NumPy array with three elements 'a', 'b', and 'c', and assign custom indexes 'first', 'second' and 'third'. Help her complete the code below.

import pandas as pd
import ______ as np
arr = np._____ (['a' , 'b' , 'c'])
s = pd._____(arr,_____=['first','second','third'])
print(s)

Explain the role of the following network devices in a network:

(I) Modem

(II) Gateway

Define the following terms with respect to RDBMS:

a. Domain

b. Tuple

Briefly explain the purpose of Boolean Indexing with respect to DataFrames. Support your answer with a suitable example.

Anjana had created a website using free design elements sourced from different creators online. She then published the site for public access but did not mention the source of the design elements used.

(i) Identify one possible violation of IPR in this situation,

(ii) Name any two licensing models that allow legal reuse of digital creative work with conditions.

Assertion (A): The output of the SQL query SELECT COUNT (name) FROM students; will differ from the output of SELECT COUNT (*) FROM students; if there are some NULL values in the name column.

Reason (R): COUNT(column_name) returns the count of NON NULL values in that column, whereas COUNT(*) returns the number of records in the table.

List any two characteristics of Pandas library in Python.

State whether the following statement is True or False:

The INSTR(stringl, string2) function in SQL returns 0 if string2 is not present as a substring in string1.

Assertion (A): Pandas DataFrame can store values of multiple data types in multiple Columns.

Reason (R): DataFrames are implemented using 2D arrays, which allows only numeric values.

What will be the result of the following SQL command?

SELECT ROUND(15.678, 2);

Nisha is using an Android app to make a voice call over the internet to her friend in another country. Which protocol is being used in this case?

In Pandas, when extracting a portion of a Series ser1 using ser1[start:end] with positional indices start and end, which of the following statements is true?

In a Pandas DataFrame, which value for axis will be used to delete a column?

Which of the following is an example of maintaining good net etiquette?

Aditya is working on a DataFrame named df. He has written the statement:

print(df.loc['S2'])

What will the above statement do?

What will be the result of the following SQL command?

SELECT LENGTH('Data Base');

(Note: There is single space between the words Data and Base.)

Which of the following is a key feature of a Static Web Page?

Which of the following is the correct expanded form of DML?

In the context of creating a Pandas Series from a dictionary, which of the following statement is correct?

CSV stands for __________ Separated Values.

State whether the following statement is True or False:

In SQL, an aggregate function returns multiple values for each column on which it is applied.

Naveen discarded various types of waste material without realizing that e-waste contains harmful substances that could pollute the environment. He wants to know which of the following will be considered as e-waste?