Answer:
Commands: commands are also known as "programs" and the program is a set of rules that performs a specific task which is executed by a computer.
Unix is an operating system. that supports multi-tasking and multi-user functionality. Unix is most widely used in all forms of computing systems such as desktop, laptop, and servers. It provides a Graphical user interface similar to windows.
The Unix operating system there are various commands. The list of five Unix commands can be given as:
1) cal
2) date
3) banner
4) who
5) whoami
1)cal:
The cal command stands for calender. It displays the date.
Syntax:
$ cal
or
$ cal [[month] year]
Example:
$ cal 10 2019
2)date:
The date command stands for date and time. It displays the system date and time.
Syntax:
$date
or
$ date[+format]
Example:
$ date +%d/%m/%y
3) banner
The banner command stands for display the text in to a large size.
Syntax:
$banner message
Example:
$banner Unix
4) who
The who command stands for display the list of users currently logged in.
Syntax:
$who
or
$who [option] … [file][arg1]
Example:
$who
5) whoami
The whoami command stands for display the user id of the currently logged-in user.
Syntax:
$whoami
Example:
$whoami
Explanation:
1)cal command display the current month and year.
2)date command display system date and time.
3)banner command display text in large size.
4)who command display the user name who currently login.
5)whoami command display user id.
Answer:
C. 220.100.100.45 to 220.100.100.46
Explanation:
The Classless IP subnetting of 220.100.100.0 begins from the fourth octet of the IP address. To get 45 subnet mask, it uses 6 bits from the fourth octet, which approximately give 64 subnets, while the remaining 2 bits are used for host IP addressing.
The useable host IP addresses are gotten from the formula '
-2', with n=2 bits.
useable host IP addresses = 2^2 - 2 = 2 addresses per subnet.
While the 12th subnet is 12 x 2^2 = 44.
This means that the 12th subnet mask starts with 220.100.100.44 (as the network address) and ends with 220.100.100.47 as broadcast IP address, while '.45' and '.46' are the assignable addresses of the subnet.
Answer:
a. 118.20.210.254
Explanation:
Here are the few characteristics of Class A:
First bit of the first octet of class A is 0.
This class has 8 bits for network and 24 bits for hosts.
The default sub-net mask for class A IP address is 255.0.0.0
Lets see if the first bit of first octet of 118.20.210.254 address is 0.
118 in binary (8 bits) can be represented as : 1110110
To complete 8 bits add a 0 to the left.
01110110
First bit of the first octet of class A is 0 So this is class A address.
For option b the first octet is : 183 in the form of bits = 10110111 So it is not class A address
For option c the first octet is 215 in the form of bits = 11010111 So it is not class A address
For option d the first octet is 255 in the form of bits = 11111111. The first bit of first octet is not 0 so it is also not class A address.
