Answer: A) 17 yrs Explanation: Let the present age of Raj and Rajitha be 4x and 9x.Then, according to question,9x = 2(9x-12)-3 => 9x = 27 => x = 3Raj's present age = 4x = 12yrs, After 5 years Raj's age will be 12 + 5 = 17 yrs.

Any two amino acids vary structure by the r-group, otherwise all amino acids are in the same structure. All amino acids have in common carboxyl group -COO , amino group -NH3+ and a hydrogen -H and a r-group which are all bonded to a central carbon.

Answer: C) 209 Explanation: We may have (1 boy and 3 girls)or(2boys and 2 girls)or(3 boys and 1 girl)or(4 boys). Required number of ways = (C16× C34) + C26×C24  + (C36× C14) + (C46)   = (24+90+80+15)  = 209.

Answer: C) cosx Explanation:   Thus, the derivative of sinx by first principle is cosx.

Answer: C) 3/4 Explanation: Let A, B, C be the respective events of solving the problem and A , B, C be the respective events of not solving the problem. Then A, B, C are independent event ∴A, B, C are independent events Now,  P(A) = 1/2 , P(B) = 1/3 and P(C)=1/4  PA=12, PB=23, PC= 34 ∴ P( none  solves the problem) = P(not A) and (not B) and (not C)                     = PA∩B∩C                    = PAPBPC         ∵ A, B, C are Independent                                          =  12×23×34                     = 14   Hence, P(the problem will be solved) = 1 - P(none solves the problem)                  = 1-14= 3/4

Answer: A) Jatin Das Explanation: Jatindra Nath Das, also known as Jatin Das, was a revolutionary and Independence activist. He embraced death in Lahore jail after fasting for 64 days in 1929 at the age of 24 yrs.

Answer: B) All living cells arise from pre-existing cells Explanation: All living cells arise from pre-existing cells is one component of the cell theory.   The Cell Theory is one of the basic principles of biology.   The Cell Theory states: 1. All living organisms are composed of cells. They may be unicellular or multicellular. 2. The cell is the basic unit of life. 3. Cells arise from pre-existing cells.

Answer: B) Flimsy Explanation: Durable means able to withstand wear, pressure.   Antonyms for Durable are Delicate, Flimsy, Short-lived.