Answer: C) 4 Explanation: N = H.C.F. of (4665 - 1305), (6905 - 4665) and (6905 - 1305) = H.C.F. of 3360, 2240 and 5600 = 1120. Sum of digits in N = ( 1 + 1 + 2 + 0 ) = 4

Answer: A) impair the racial qualities of future generations either physically or mentally Explanation: Eugenics is the study of altering human beings by changing their genetic components.   It is the study of the agencies under social control that may improve or impair the racial qualities of future generations either physically or mentally.

Answer: D) 0 Explanation: As we know we have 10 letter and 10 different address and one more information given that exactly 9 letter will at the correct address....so the remaining one letter automatically reach to their correct address P(E) = favorable outcomes /total outcomesHere favorable outcomes are '0'.So probability is '0'.

Answer: A) Induce high voltage Explanation: When the switch is ON, in a tube light choke is nothing but the coil/ballast ( inductor) which is used to induce the high voltage across it. as we know that inductor has property to induce high voltage for the brief period of time, this high voltage is required to ionize the gases in the starter. Then gas inside the starter gets ionized due to this full voltage and heats the bimetallic strip that is caused to be bent to connect to the fixed contact. Current starts flowing through the starter. Although the ionization potential of the neon is the little bit more than that of the argon but still due to small electrode gap high voltage gradient is appeared in the neon bulb and hence glow discharge is started first in a starter. As voltage gets reduced due to the current causes a voltage drop across the inductor, the strip cools and breaks away from the fixed contact. At that moment a large L di/dt voltage surge comes across the inductor at the time of breaking. This high valued surge comes across the tube light electrodes and strikes penning mixture (mixture argon gas and mercury vapor). Gas discharge process continues and current gets the path to flow through the tube light gas only due to low resistance as compared to the resistance of starter.

Answer: D) DNA Replication Explanation: The First step of Bacterial Replication is DNA Replication. DNA must be copied in order to proceed.

Answer: B) Sole Explanation: All shoes have a sole of some sort.Not all shoes are made of leather (choice b); nor do they all have laces (choice c).Walking (choice d) is not essential to a shoe.

Answer: A) 31 years Explanation: Let the present age of Pinky be x years   Then the age of Mary is x - 12 years   After 3 years,   Ratio of  MaryPinky = x - 9x + 3 = 58   8x - 72 = 5x +15   => 3x = 87   => x = 29   => Age of Pinky = 29 years   => Age of Mary = 29 - 12 = 17 years   Present age of Sam = 29 + 17 = 46   Before 15 years Sam age = 46 - 15 = 31 years.

Answer: D) 4 kmph Explanation: Speed of Man = 4.5 kmphSpeed of stream = 1.5 kmphSpeed in DownStream = 6 kmphSpeed in UpStream = 3 kmphAverage Speed = (2 x 6 x 3)/9 = 4 kmph.