Answer: A) Chemical Explanation: In rusting the Iron ore make a chemical reaction with the oxygen in the presence of water and environmental or atmospheric moisture to produce an Iron oxide. Iron oxide is otherwise called as rust. The rusting of iron is a chemical change because it is two substances reacting together to make a new substance.

Answer: D) 36 years Explanation: Let present ages of Sushanth = w, Krish = x, Rishi = y and Rohit = z , thenw + x + y = 43 x 3 = 129 ---(i) andw + y + z = 49 x 3 = 147 ---(ii)Subtracting (i) from (ii), (w+y+z) - (w+x+y) = 147 - 129 , z - x = 18 ---(iii)Given Rohit's age=z=54, so from (iii), x = 54 - 18 = 36.Therefore, Krish age is 36 years.

Answer: C) 22 nd March Explanation:

Answer: A) a wave reflects upon itself Explanation: A standing wave also known as a stationary wave, is a wave in which its peaks or any other point on the wave do not move spatially. This phenomenon can occur because the medium is moving in the opposite direction to the wave, or it can arise in a stationary medium as a result of interference between two waves traveling in opposite directions. The most common cause of standing waves is the phenomenon of resonance, in which standing waves occur inside a resonator due to interference between waves reflected back and forth at the resonator's resonant frequency.   Hence, standing wave occurs when a wave reflects upon itself.

Answer: B) Mumbai, 1885 Explanation: The first session of Indian National Congress was held from 28–31 December 1885, in Mumbai and was attended by 72 delegates. Womesh Chandra Bonnerjee was the first president of the Indian National Congress (INC), a voice of Indian opinion to the British government.

Answer: D) Nucleus Explanation: In the cell, transcription occurs in the nucleus in the presence of DNA. Terms transcription and translation in biology are generally related to the DNA and its properties. Human cells replicate. In order to do that, they have to produce the same constituents for the new cell that is to be made. The only way to do that is by producing proteins. The proteins are produced in the process that is called protein synthesis. The first step is in the nucleus where a particular gene is being expressed so it enables all protein factors to come and to replicate that part of a chromosome. This is finished when mRNA, the same single-stranded genetic code of a particular gene, is formed. This is transcription. Right after that, the mRNA enters the cytoplasm through nuclear pores. There, it could be translated into proteins by ribosomes. This process is called translation.   Hence, Transcription occurs in the nucleus, whereas translation occurs in the cytoplasm.

Answer: A) 1, 5 – hexadiene Explanation: 3 – Hexanol: There is no alcohol stretch present in the spectrum. Therefore, the above structure is not suitable for the given spectrum.   Trans – 4 – octene: There is no vinyl bending present in the spectrum. Therefore, the above structure is not suitable for the given spectrum. 1, 5 – hexadiene: The vinyl bending and other stretches were matched with the above structure.     Hence, the c = c stretch, vinyl bending and stretch were matched with the above structure. Therefore, the given spectrum belongs to 1, 5 – hexadiene.