Answer: C) 48.88% Explanation: Number of runs made by running = 180 - (11 x 4 + 8 x 6)= 180 - (92)= 88Now, we need to calculate 88 is what percent of 180.⇒88180×100  = 48.888%.

Answer: B) 128 sq.cm Explanation: Area =    = 96   Sum of Area =

Answer: C) Nucleic acids Explanation: DNA stands for Deoxyribo nucleic acid. It is a nucleic acid made up of monomeric unit called Nucleotide. A nucleotide consist of - a) Sugar - Deoxyribose in DNA ( ribose in RNA) b) An organic base- Adenine, cytosine, guanine.

Answer: C) 4 : 5 Explanation: Let their present ages be 13x and 17x.Then, 13x-4/17x-4 = 11/15. Solving this, we get x = 2.Required ratio = 13x2 + 6/17x2 + 6 = 32/40 = 4/5.

Answer: A) +6 Explanation: We will rewrite the formula as an equation. 2K + 2Cr + 7O = 0 The zero comes from there being no overall charge on the compound. Each oxidation number is represented by the element's symbol. Since this compound is not a peroxide or superoxide, the oxidation value for O is -2 K being in group 1 has a +1 charge and therefore has an oxidation number of K is +1 Now, by putting known values in we have: 2(+1) + 2(Cr) + 7(-2) = 0 2 + 2Cr -14 = 0 2Cr = +12 Cr = +6.

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: A) 1 : 3 Explanation: Let the speed of the boat in still water is 'w' Speed of the current is 'c' Let the distance between two places is 'd' According to the question, motorboat takes half time to cover a certain distance downstream than upstream. dw+c = 12dw-c => 2w - 2c = w + c => w = 3c => c : w = 1 : 3   Hence, the ratio between rate of current(c) and rate of boat in still water(w) = 1 : 3

Answer: B) 15 Explanation: Here crossing is AaBbCc x AaBbCc As it is trihybrid cross, we know, Number of zygotes formed = 4n, where n = 3 43 = 64 Given ratio of offsprings = 1 : 6 : m : 20 : m : 6 : 1 Now,  1 + 6 + m + 20 + m + 6 + 1 = 64 34 + 2m = 64 2m = 30 => m = 15.