Question Discussion & Solution

The correct answer is Mercury.

Key Points

• Mercury is the closest planet to the Sun.
• The planet probably received this name because it moves so quickly across space.
• Temperature variations on Mercury are the most extreme in the solar system ranging from 90 K to 700 K.
• Mercury is the second densest major body in the solar system, after Earth.

Important Points 

• The solar system is made up of the sun and everything that orbits around it, including planets, moons, asteroids, comets, and meteoroids.
  • It extends from the sun, called Sol by the ancient Romans, and goes past the four inner planets, through the Asteroid Belt to the four gas giants and on to the disk-shaped Kuiper Belt and far beyond to the teardrop-shaped heliopause.
  • Scientists estimate that the edge of the solar system is about 9 billion miles (15 billion kilometers) from the sun.
  • Beyond the heliopause lies the giant, spherical Oort Cloud, which is thought to surround the solar system.

Additional Information 

•  The sun is at the center of our solar system and is its largest object, accounting for 99.8% of the solar system's mass.
  • Our sun is a giant, raging ball of fire powered by nuclear reactions, and it provides the energy that sustains life on Earth.
  • The life-giving star is a yellow dwarf star made up of gas: about 91% hydrogen and 8.9% helium, according to NASA.
  • Compared with other stars, the size of the sun is relatively small and it's just one of the hundreds of billions of stars in our home galaxy, the Milky Way. 

CONCEPT:

Metals Have Luster:

• Metals, in their pure state, have a shining surface. This property is called metallic luster.
• All the metals have a luster and shiny property except Lead.
• If we polish metals most of them having a reflecting surface i.e. Gold, Silver, etc.

EXPLANATION:

• When light shines on a lustrous metal, the loosely bound electrons reflect incoming light, giving the metal a shiny appearance. Therefore option 3 is correct.

The correct answer is between 13 to 20 days.

Key Points

• The life span of the WBC is between 13 to 20 days. 
• The life span of the RBC is 20-120 days and it gets destroyed in the spleen area of the human body to recycle Iron content.
• The life span of the blood platelets is 3-5 days. 
• WBC's are mainly responsible for the protection of the body from diseases.

Additional Information

 Important Points

• WBCs are also called leukocytes or white corpuscles.
• The life span of WBCs is 13 to 20 days.
• Total WBCs count ranges from 4,500 to 10,000.
• WBCs are a cellular component of the blood that lacks hemoglobin, has a nucleus, is capable of mobility, and producing antibodies.
• They act as a " Soldier or Guard " of our body.
• The size of WBCs is 12 to 17 µm in Diameter and about three times RBCs.
• WBCs do not have any Fixed shape, it may be circular, rhomboid, or any other shape.

Concept:

Block-container is a block-level formatting object that wraps blocks into a bigger block area with additional attributes to control its size, writing-mode, reference-orientation, etc. Its content is limited to a sequence of blocks only.

A "block-container" formatting object has the following main attributes:

• width="..." and height="..." - Optional attributes to specify the width and height of output block area. Default values are automatically calculated.
• writing-mode="..." - Similar to region-body[@writing-mode].
• reference-orientation="..." - Similar to region-body[@reference-orientation].
• Other attributes are similar to "block" elements.

LAN :

• LAN stands for Local Area Network.
• It's a group of computers which belong to the same organisation, and are linked within a small geographic area using a network using the same technology (Ethernet).
• E.g. Wi-Fi

MAN :

• MANs (Metropolitan Area Networks) connect multiple geographically nearby LANs to one another at high speeds.
• A MAN lets two remote nodes communicate as if they were part of the same local area network.
• E.g. microwave antenna on a TV news van, extended high in the air, beaming video and sound back to the main TV studio.

WAN:

• A WAN (Wide Area Network or extended network) connects multiple LANs to one another over great geographic distances.
• WANs operate using routers, which can "choose" the most appropriate path for data to take to reach a network node.
• E.g.: Internet

PAN:

• A personal area network (PAN) is a network used for data transmission amongst devices such as computers, telephones, tablets, personal digital assistants, fax machines and printers, that are located close to a single user

E.g. Bluetooth