We know a proverb that An apple a day keeps the doctor away. To keep the doctor away from her, he gave seven apples, each apple a day.

An IP address (internet protocol address) is a numerical representation that uniquely identifies a specific interface on the network. Addresses in IPv4 are 32-bits long. This allows for a maximum of 4,294,967,296 (2^32) unique addresses. Addresses in IPv6 are 128-bits, which allows for 3.4 x 1038 (2^128) unique addresses.

IP addresses available to the internet are classified as Public.

The product of a number and its reciprocal is always equals to 1.

For Example : Let the number be 4.

Now, its reciprocal is 1/4

Hence, required product = 4 x 1/4 = 1.

Now, take the number as -15.

Then its reciprocal is -1/15

Required product = -15 x -1/15 = 1.

Hence, the product of a number and its reciprocal is 1.

The first identification of Nipah virus as a cause of an outbreak of encephalitis was reported in 2001 in Meherpur district of Bangladesh. Since, then Outbreaks of the deadly Nipah virus has been recorded almost every year in selected districts of Bangladesh.

Drinking raw date palm sap and contact with a case were identified as the major risk factors for acquiring the disease.

A clipboard is a temporary storage area for items that the user wants to cut or copy from one place to another.

For example, in a word processor application, the user might want to cut text from one part of a document and paste it in another part of the document or somewhere else, it is temporarily stored in clipboard.

Let the speed of the boat = p kmph

Let the speed of the river flow = q kmph

From the given data,

2 x 28p + q = 28p - q

=> 56p - 56q -28p - 28q = 0

=> 28p = 84q

=> p = 3q.

Now, given that if

$$\begin{gathered} 283q + 2q + 283q - 2q = 67260 \\ => 285q + 28q = 67260 \\ => q = 3 kmph \\ => x =3q = 9 kmph \end{gathered}$$

Hence, the speed of the boat = p kmph = 9 kmph and the speed of the river flow = q kmph = 3 kmph.

What is Dipole :

when two atoms in a molecule have substantially different electronegativity: One atom attracts electrons more than another, becoming more negative, while the other atom becomes more positive.

A periscope is an optical instrument that uses a system of prisms, lenses, or mirrors to reflect images through a tube.

Light from a distant object strikes the top mirror and is then reflected at an angle of 90 degrees down the periscope tube. At the bottom of the periscope, the light strikes another mirror and is then reflected into the viewer’s eye.

Hence, A periscope works by the principle of Total internal reflection.