Polarity ::  The polarity of a molecule defines its other physical properties such as melting point, boiling point, surface tension, vapor pressure etc... Simply, polarity occurs when the electron distribution in a molecule is asymmetric. This results in a net dipole moment in the molecule. One end of the molecule is charged negative while the other gets a positive charge.   The polarization of a molecule greatly depends on the shape of the molecule. A diatomic molecule like HF mentioned above has no issue of shape. The net dipole moment is only due to the uneven distribution of electrons between the two atoms. However, when there are more than two atoms involved in making a bond, there are many complexities.   The water molecule is of bent shape. Therefore, when the two pair of electrons shared by oxygen with two hydrogen atoms is pulled towards oxygen, the net dipole moment results in the direction of the oxygen atom. There is no other force to cancel out the resultant dipole moment. Hence, the water molecule is highly polar.   Ammonia molecule is of a pyramid shape and the electronegative N atom pulls the electrons towards itself. The three N-H bonds are not in the same plane; hence the dipole moments created do not get canceled out. This makes ammonia a polar molecule.   However, the dipole moments sometimes get canceled due to the shape of the molecules, making the molecule non-polar. Carbon dioxide is such a molecule.

Answer: D) Contagious Explanation: A Disease which spreads by contact are Contagious. Infectious diseases : These are caused by microscopic germs such as bacteria or viruses that get into the body and cause problems. Some but not all infectious diseases spread directly from one person to another. Infectious diseases that spread from person to person are said to be contagious. Some infections spread to people from an animal or insect, but are not contagious from another human.  Contagious diseases such as the flu, colds, or strep throat spread from person to person in several ways. One way is through direct physical contact, like touching or kissing a person who has the infection. Another way is when an infectious microbe travels through the air after someone nearby sneezes or coughs. Fatal Diseases : Diseases leading to failure or disaster. Incurable Diseases : Diseases of a sick person not able to be cured.

Answer: B) 8 % Explanation: Let the price of 1 litre of diesel be Rs.x and let Karthik initially buy 'y' litres of diesel. Therefore, he would have spent Rs. xy on diesel. When the price of diesel increases by 25%, the new price per litre of diesel is 1.25x. Karthik intends to increase the amount he spends on diesel by 15%.i.e., he is willing to spend xy + 15% of xy = 1.15xy Let the new quantity of diesel that he can get be 'q'.Then, 1.25x x q = 1.15xyOr q = (1.15/1.25)y = 0.92y. As the new quantity that he can buy is 0.92y, he gets 0.08y lesser than what he used to get earlier. Or a reduction of 8%.

Answer: C) 37 Explanation: The number of liters in each can = HCF of 80, 144 and 368 = 16 liters.Number of cans of Maaza = 368/16 = 23Number of cans of Pepsi = 80/16 = 5Number of cans of Sprite = 144/16 = 9The total number of cans required = 23 + 5 + 9 = 37 cans.

Answer: A) Iran Explanation:

Answer: D) All the above Explanation: The central nervous system CNS is responsible for integrating sensory information and responding accordingly. It consists of two main components::  1. The brain  2. The spinal cord The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement. The brain can be divided into four main lobes: temporal, parietal, occipital and frontal.   The spinal cord serves as a conduit for signals between the brain and the rest of the body.

Answer: A) cruise Explanation: Cruise = a sea voyage for pleasure. All other words are related to ‘journey on land, sea with an aim’.

Answer: C) b only Explanation: Since half of the four children are girls, two must be boys. It is not clear which children have blue or brown eyes. So only statement (b) follows.