Answer: A) 5100 sq.m Explanation: Let the breadth of floor be 'b' m. Then, length of the floor is 'l = (b + 25)' Area of the rectangular floor = l x b = (b + 25) × b According to the question, (b + 15) (b + 8) = (b + 25) × b b2 + 8b + 15b + 120 = b2 + 25b 2b = 120 b = 60 m. l = b + 25 = 60 + 25 = 85 m.   Area of the floor = 85 × 60 = 5100 sq.m.

Answer: D) Covalent- network Explanation: Graphite is a covalent-network type of crystalline solid.   There are two main categories of solids. 1. Crystalline solids and 2. Amorphous solids. Crystalline solids are those in which the atoms, ions, or molecules that make up the solid exist in a regular, well-defined arrangement. There are four types of crystalline solids : Ionic solids :— Made up of positive and negative ions and held together by electrostatic attractions. They’re characterized by very high melting points and brittleness and are poor conductors in the solid state. An example of an ionic solid is table salt, NaCl. Molecular solids :— Made up of atoms or molecules held together by London dispersion forces, dipole-dipole forces, or hydrogen bonds. Characterized by low melting points and flexibility and are poor conductors. An example of a molecular solid is sucrose. Covalent-network (also called atomic) solids :— Made up of atoms connected by covalent bonds; the intermolecular forces are covalent bonds as well. Characterized as being very hard with very high melting points and being poor conductors. Examples of this type of solid are diamond and graphite, and the fullerenes. As you can see below, graphite has only 2-D hexagonal structure and therefore is not hard like diamond. The sheets of graphite are held together by only weak London forces! Metallic solids :— Made up of metal atoms that are held together by metallic bonds. Characterized by high melting points, can range from soft and malleable to very hard, and are good conductors of electricity.

Answer: C) Mobilephone Explanation: Given 8, 9, 1, 11 letters indicates HOME which is residence 7, 2, 9, 5 indicates POOL where we can swim 1, 4, 5, 11 indicates MILE which is unit of distance 10, 9, 3, 6, 5 is NOBEL which is an International Prize 6, 11 are 'e' and 2, 9 are 'o' are same With all the above hints the word is MOBILEPHONE.

Answer: C) 1/4 Explanation: Non collision can happen only when all the cars move in same direction. That is either all cars moving in clockwise direction or all cars moving in anti clockwise direction.P(all cars not colliding) = P(all cars moving in the same direction) = P(all cars moving in clockwise direction)  +  P(all cars moving in anticlockwise direction) = [p(A --> C) x p(C --> B) x p(B --> A)]  +  [p(A --> B) x p(B --> C) x p(C --> A)] = [1/2 x 1/2 x 1/2] + [1/2 x 1/2 x 1/2] = 1/8 + 1/8 = 1/4

Let the present age's of mother be 'M' and that of her son be 'S'. According to the given data in the question, M - 5 = 3(S - 5) F - 3S = -10  ...............(1) Then given , M + 5 : S + 5 = 11 : 5  => 5M - 11S = 30 ..............(2)   From (1) & (2), we get S = 20 Then by substituting S = 20 in (1) or (2), we get M = 50.   Hence, the present age of mother is M = 50 years.

Answer: D) Football Explanation:

Answer: B) Rudra Explanation:

Answer: D) All the above Explanation: Prokaryotic cells lack a nucleus and do not have an extensive system of interior membranes. They are encased in a cell wall and many contain external structures such as a capsule, flagellum, or pili. Prokaryotes – have a relatively uniform interior that is not subdivided by internal membranes.