Question Discussion & Solution

All are divisible by 10 except 25.

If '+' means 'divide by', '-' means 'add to', '×' means 'subtract from' and '/' means 'multiply by',

[{(20 × 6) × (7 / 2)} + (3 - 2)] / 5

We put the right symbol given is the question-

= [{(20 - 6) - (7 × 2)} / (3 + 2)] × 5

Now apply BODMAS rule

= [{14 - 14} / 5] × 5

= [0 / 5] × 5

= 0

Hence, "0" is the correct answer.

The correct answer is option 3 i.e. the Atomic Number

• The periodic table is based on Atomic Number.
• The atomic number is the number of protons found in the nucleus of every atom of that element. 
• The periodic table is managed by the International Union of Pure and Applied Chemistry, or IUPAC.
• In 1869, Dimitri Mendeleev included 63 known elements arranged according to increasing atomic weight. But there were many elements he could not place in the periodic table and with the discovery of new noble elements, there was a need to arrange the elements. Henry Moseley later arranged the elements in the periodic table by their number of protons rather than their atomic weights.
• The modern periodic table orders the elements according to increasing atomic number rather than increasing atomic weight.
• There are 118 elements in a periodic table. There are seven periods and eighteen groups in the modern periodic table.
• On moving from left to right in a period, the size of atoms(atomic size) decreases.
• On moving from left to right in a period, the metallic character of elements decreases, whereas the non-metallic character increases.
• While going down in a group of the periodic table, the size of atoms increases (or atomic size increases).
• While going down in a group of the periodic table, the metallic character of elements increases.
• Electronegativity and reactivity of non-metals increase along the period and decrease down the group.

Running, Swimming, Dancing requires some body movement from one place to other.

While, Breathing does not require movable body movement.

Hence, Breathing is the correct answer.

Hypertext transfer protocol (HTTP):

• HTTP is used to access data on the world wide web. HTTP functions as a combination of FTP and SMTP. HTTP uses the services of TCP port number 80. HTTP is a stateless protocol.
• HTTP prior to version 1.1 specified a non-persistent connection, while a persistent connection is a default.
• In a non-persistent connection, one TCP connection is made for each request/ response. The client opens a TCP connection and sends a request and server sends the response then closes the connection.

File Transfer Protocol (FTP):

• FTP stands for file transfer protocol. It is provided by TCP/IP for copying a file from one host to another. FTP can transfer a file through one of the following three modes: stream mode, block mode and compressed mode. Stream mode is the default mode.
• FTP uses two TCP connections one for data and another for control.

Simple Transfer Protocol (SMTP):

• SMTP is a push protocol, it can push the messages from the client to the server only.
• SMTP uses one TCP connection at a time

TELNET:

• TELNET is a client/ server application that allows a user to log on to a remote machine, giving the user access to the remote system.
• TELNET uses one TCP connection at a time.

Important Point:

Option 1 is not correct since HTTP might have more than one TCP connections for a single web page.