Answer: A) Distillation Explanation: The first step in the refining of petroleum is distillation i.e,  the fractionation of crude oil in atmospheric and vacuum distillation towers. The first process petroleum refinery is known as distillation. In this process, crude oil is heated and fed into a distillation column. As the temperature of the crude oil in the distillation column rises, the crude oil separates itself into different components, called "fractions." The fractions are then captured separately. Each fraction corresponds to a different type of petroleum product, depending on the temperature at which that fraction boils off the crude oil mixture.

Answer: D) 320 Explanation: 1 to 300 = 300 numbers squares btwn 1 to 300 = 1,4,9,16,25,36,49.....289 i.e, total 17cubes = 1,8,27,64,125,216 i.e, 5 now 1 and 64 are common so total numbers that should be removed ( 17+5-2= 20 )total 20 term removed so 300th term would be 320

Answer: B) 23 Explanation: Let the greater and smaller number be p and q respectively. 4q = p + 5 ------ (I) p = 3q+2 ------- (II) From equation (I) and (II) q = 7 p = 23

Answer: B) 178 cm Explanation: Area of square = 40 x 40 = 1600 sq.cm Given that the areas of Square and Rectangle are equal => Area of rectangle = 1600 Sq.cm We know that, Area of rectangle = L x B Given L = 64 cm Breadth of rectangle = 1600/64 = 25 cm Perimeter of the rectangle = 2(L + B) = 2(64+25) = 178 cm.

Answer: D) 3/8 Explanation: 3/4 divided by 2 = 3/4/2 = 3/4x2 = 3/8.   Hence, 3/4 divided by 2 is equal to 3/8.

Answer: C) Fe Explanation: In chemistry, the term transition metal has three possible meanings: The IUPAC definition defines a transition metal as "an element whose atom has a partially filled d sub-shell, or which can give rise to cations with an incomplete d sub-shell". Any of the set of metallic elements occupying a central block (Groups IVB–VIII, IB, and IIB, or 4–12) in the periodic table, e.g. iron, manganese, chromium, and copper. Chemically they show variable valency and a strong tendency to form coordination compounds, and many of their compounds are coloured.   Here in the given options, only iron (Fe) is a transition metal since Strontium is an alkaline earth, arsenic is a metalloid, hydrogen is (normally) a diatomic gas.

Answer: A) Amino acids Explanation: Proteins are long chains of Amino acids. That is in brief, Amino acids are the monomers of Proteins. Amino acids are compounds which contain both an amino group and a carboxylic group. Proteins are made up of 20 essential amino acids. Monomer means a small molecule of an organic substance i.e, building block in general.

Answer: A) Decrease in the thickness of ozone layer in Stratosphere Explanation: