Answer: A) 15 Explanation: Using BODMAS Rule, First solve division, mutiplication and Addition So here 10/2 = 5 Then 2 x 5 =  10 Now, 5 + 10 = 15.   Hence, 5 + 2 x 10/2 = 15.

Answer: A) 1/3 Explanation: In a family with 2 children there are four possibilities:1) the first child is a boy and the second child is a boy (bb)2) the first child is a boy and the second child is a girl (bg)3) the first child is a girl and the second child is a boy (gb)4) the first child is a girl and the second child is a girl (gg) But already given that one child is boy. So we have three possibilities of (bb)(bg)(gb).n(E)= both are boys=BB=1n(S)= 3Required probability P = n(E)/n(S) = 1/3.

Answer: A) H and Br Explanation: Only H and Br form Polar Covalent Bond.   Covalent bonding: Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability. 1. Polar Covalent Bond 2. Nonpolar Covalent Bond   1. Polar Covalent Bond: A Polar Covalent Bond is created when the shared electrons between atoms are not equally shared. This occurs when one atom has a higher electronegativity than the atom it is sharing with. The atom with the higher electronegativity will have a stronger pull for electrons (Similiar to a Tug-O-War game, whoever is stronger usually wins). As a result, the shared electrons will be closer to the atom with the higher electronegativity, making it unequally shared.   2. Nonpolar Covalent Bond: A Nonpolar Covalent Bond is created when atoms share their electrons equally. This usually occurs when two atoms have similar or the same electron affinity. The closer the values of their electron affinity, the stronger the attraction. This occurs in gas molecules; also known as diatomic elements. Nonpolar covalent bonds have a similar concept as polar covalent bonds; the atom with the higher electronegativity will draw away the electron from the weaker one.   Here H and H and N and N form Non-polar covalent bonds. Na and Br form the ionic bond.

Answer: C) 8 min Explanation: The light from the sun takes about 8 minutes to reach the Earth after it has been emitted from the sun's surface.   The time it takes for light to reach planets in our Solar System varies from about 3 minutes for Mercury to about 5.3 hours for Pluto.

Answer: C) Survey of India Explanation: Survey of India publishes maps and the unrestricted category maps can be obtained at very affordable prices from its several Geospatial data centers. Restricted category maps require due approval from government authorities. Many other rules govern the sale and use of Survey of India maps. Only an Indian citizen may purchase topographic maps and these may not be exported from India for any reason.   The Survey of India is India's central engineering agency in charge of mapping and surveying, set up in 1767. Its members are from Survey of India Service cadre of Civil Services of India. It is headed by the Surveyor General of India.

Answer: A) the mass of the liquid displaced Explanation: Buoyancy or Upthrust, is an upward force exerted by a fluid that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.

Answer: D) 3/4 Explanation: Let S be the sample space.Here n(S)= 23 = 8Let E be the event of getting atmost two heads. Then,n(E) = {(H,T,T), (T,H,T), (T,T,H), (H,H,T), (T,H,H), (H,T,H)}Required probability = n(E)/n(S) = 6/8 = 3/4.

Answer: D) 15.25 yrs Explanation: Total ages of 80 boys = 15 x 80 = 1200 yrs.Total age of 16 boys = 15 x 16 = 240 yrsTotal age of 25 boys = 14 x 25 = 350 yrs.Average age of remaining boys = 1200 - (240+350) / 80 - (25+15) = 610/41 = 15.25 yrs.