Commerce (English Medium) कक्षा १२ - CBSE Question Bank Solutions

Expand the following:

ISP

What is data communication?

Why is a computer considered to be safe if it is not connected to a network or the Internet?

What is a computer virus? Name some computer viruses that were popular in recent years.

How is a computer worm different from a virus?

How is Ransomware used to extract money from users?

How did a Trojan get its name?

How does adware generate revenue for its creator?

How is a Virtual Keyboard safer than an On-Screen Keyboard?

List and briefly explain different modes of malware distribution.

List some common signs of malware infection.

List some preventive measures against malware infection.

What are the main components of data communication?

Assertion (A): CSV (Comma Separated Values) is a file format for data storage that looks like a text file.

Reason (R): The information is organized with one record on each line and each field is separated by a comma.

Atharva is a Python programmer working on a program to find and return the maximum value from the list. The code written below has syntactical errors. Rewrite the correct code and underline the corrections made.

def max_num (L):
        max=L(O)
        for a in L:
                if a > max
                 max=a
        return max

Differentiate between CHAR and VARCHAR data types in SQL with appropriate examples.

Write one difference between CSV and text files.

In a table in the MYSQL database, an attribute A of datatype varchar(20) has the value “Keshav”. The attribute B of datatype char(20) has the value “Meenakshi”. How many characters are occupied by attribute A and attribute B?

The code given below accepts a number as an argument and returns the reverse number. Observe the following code carefully and rewrite it after removing all syntax and logical errors. Underline all the corrections made.

define revNumber (num) :
      rev = 0
      rem = 0
      While num > 0:
            rem ==num %10
            rev = rev*10 + rem
            num = num//10
            return rev
print (revNumber (1234))

Kabir wants to write a program in Python to insert the following record in the table named Student in MYSQL database,

SCHOOL:

• rno(Roll number) - integer
• name(Name) - string
• DOB (Date of birth) - Date
• Fee - float

Note the following to establish connectivity between Python and MySQL:

• Username - root
• Password - tiger
• Host - localhost

The values of fields rno, name, DOB and fee has to be accepted from the user. Help Kabir to write the program in Python.