Answer: A) 2 Explanation: In each row, the second figure is obtained from the first figure by adding two mutually perpendicular line segments at the centre and the third figure is obtained from the first figure by adding four circles outside the main figure.

Answer: D) 1/14 Explanation: The 8 letters can be written in 8! ways.n(S) = 8!Let E be the event that the letters b,c,d,e always come together when the first 8 alphabets are written down.Now the letters a, (bcde), f, g and h can be arranged in 5! ways.The letters b,c,d and e can be arranged themselves in 4! ways.n(E) = 5! x 4!Now, the required P(E) = n(E)/n(S) = 5! x 4!/8! = 1/14Hence the answer is 1/14.

Answer: B) Heterogeneous Explanation: Blood is a heterogeneous mixture because the blood cells are physically separate from the blood plasma. The cells have different properties than the plasma. The cells can be separated from the plasma by centrifuging, which is a physical change.

Answer: A) 27 % Explanation: Let the percentage of benzene = X(30 - X)/(X- 25) = 6/4 = 3/2 => 5X = 135  X = 27 So, required percentage of benzene = 27 %

Answer: B) 16 Explanation: Let the third proportion to 9 & 12 be 'x'. => 9:12 = 12 :p => p = 12x12/9 = 16.

Answer: C) L Explanation: 13 x 2 = 26 => Z (opposite side) 12 x 2 = 24 => X (opposite side) 13 x 1 = 13 => M (opposite side) 12 x 1 = 12 => L (opposite side)

Answer: D) 34 Explanation: The given series follows the pattern that, 18, 97, 26, 91, ?, 83 => 18 + 8 = 26 => 97 - 8 = 91 => 26 + 8 = 34 => 91 - 8 = 83 Hence, the missing number is 34.

In chemistry rusting is called as oxidation. Oxidation is a chemical process where metal gains oxygen and become oxide. 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.    Rusting would only be a physical change if iron molecules remained pure iron throughout the process.