Question Discussion & Solution

Important Points

Email bomb

It is an attack on your inbox that involves sending massive amounts of emails to your address. Sometimes these messages are complete gibberish, but more often they’ll be confirmation emails for newsletters and subscriptions.

Additional Information

Spoofing 

It is the act of disguising a communication from an unknown source as being from a known, trusted source. Spoofing can apply to emails, phone calls, and websites, or can be more technical, such as a computer spoofing an IP address, Address Resolution Protocol (ARP), or Domain Name System (DNS) server.

Smurf Attack

It is a form of a DDoS attack that causes packet flood on the victim by exploiting/abusing ICMP protocol. When deployed, large packets are created using a technique called “spoofing”. The phony source address that is now attached to these packets becomes the victim, as their IP is flooded with traffic. The small ICMP packet generated by the tool causes big trouble for a victim, hence the name Smurf.

Ping storm

It is a condition in which the Internet ping program is used to send a flood of packets to a server to  test its ability to handle a high amount of traffic or, maliciously, to make the server inoperable

Hence Option 1 is correct

Key PointsBiogas:

• Biogas is an emerging renewable, non-conventional energy source that is obtained through the degradation of organic matter by bacteria under anaerobic conditions.
• The major constituent of biogas is Methane.
• Biogas is usually made up of around 50-70% methane (CH4) and 25-45% carbon dioxide (CO2), with other gases such as hydrogen (H2), hydrogen sulphide (H2S), watervapour (H2O), Nitrogen (N2), oxygen (O2), ammonia (NH3) making up the rest.
• It is released when Cow, Buffalo, and Pig manure is processed anaerobically i.e. in the absence of Oxygen.
• Biogas can be used for Space Heating, Generation of Electricity, Fuel for Cooking, etc.

Important Points

Advantages of Biogas - 

• ​Biogas burns without smoke; hence no harmful gas such as CO₂, CO, NO₂, and SO₂ are evolved.
• The slurry produced after the production of biogas is used as manure in fields.
• The method of disposal is safe and efficient and hence no space is wasted in the form of landfills.
• Biogas plants require very little installation costs and become self-sufficient in a span of 3-4 months.
• Work opportunity for thousands of people is created, especially in rural areas.

Thus, Biogas is a non-conventional type of natural resource.

Additional Information

There are basically two sources of energy:

The correct answer is Software program.

• An operating system is system software that manages computer hardware, software resources, and provides common services for computer programs. Operating systems are found on many devices such as a computer, mobile phones, video games etc.
• Software program
  • It is a set of instructions, or a set of modules or procedures, through which computer operation is performed.
  • It is often called a software application and a software product.

Additional Information

• Computer system
  • A Computer system is usually defined as a combination of both hardware and software working together.
  • Hardware is the physical components of a computer and software is the programs that run on a computer.
• Network
  • It is a collection of computers, servers, mainframes, network devices, peripherals, or other devices connected to one another to allow the sharing of data.
  • E.g - The Internet, often referred to as the ‘Net’, consists of a complex network of computers connected by high-speed communication technologies like satellites, microwave devices, etc.
• Hardware device
  • Computer hardware includes the physical parts of a computer, such as a case, central processing unit (CPU), monitor, mouse, keyboard, computer data storage, graphics card, sound card, speakers and motherboard.
  • It accepts the data (input) from the user.
  • The computer has memory chips, which are designed to hold data until it is needed.
  • It processes this data into information. The computer has an electronic brain called the Central Processing Unit, which is responsible for processing all data into information according to the instructions given to the computer.
  • It then returns the processed information (output) to the user.

Concept:

• Water Harvesting: Water harvesting is a practice to conserve water by collecting rainwater in an organized way.
  • The rainwater is not allowed to flow and get wasted but collected in tanks.
  • The main purpose however is not the collection but the enhancement of groundwater level.  
  • The collected water through tubes is made to recharge groundwater.
  • Maintenance of groundwater is long term sustainable structure for water conservation.

Here the logic is the methods which consumes water:

Explanation:

Kneading:

• Kneading is a process in the making of dough by mixing water and flour.
• Example: Kneading dough for roti. 
• Consumes water

Swimming also need water to do so.

Washing clothes is also a process that consumes.

While combing hair, no need of water.

The relation is:

1) Sports : Ground → Sports are organised in ground.

2) Rubber : Eraser → Rubber is used to erase writings on paper.

3) Cinema : Screen → Cinema is shown on screen

4) Drama : Stage → Drama is played on stage.

Hence, Rubber : Eraser is the correct answer.