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: B) Jairam Thakur Explanation: Jairam Thakur was sworn-in as the Chief Minister of Himachal Pradesh on 27th December 2017 after virbhadra Singh. The cabinet, including Thakur, were administered the oath of office and secrecy by Governor Acharya Dev Vrat at the historic Ridge Ground in Shimla, the capital city of Himachal Pradesh.   Jai Ram is the first chief minister from the second largest Mandi district and the 14th chief minister and sixth person to adorn the office of the chief minister.

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: 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: D) 100 min Explanation: Work done by the third pipe in 1 min = 1/50 - (1/60 + 1/75) = - 1/100.[-ve sign means emptying] The third pipe alone can empty the cistern in 100 min.

Answer: A) Distance Explanation: Light Year is related to Distance. It is the unit of Distance. It is about 9.5 Trillion Kms or 5.9 Trillion miles.   It is the distance that light travels in vaccum in one julian year i.e, 365.25 days.

Answer: B) Methanol (CH3OH) Explanation: Chemical Compounds with stronger intermolecular forces have higher boiling points.   The order of strengths of intermolecular forces is:  London dispersion < dipole-dipole < H-bonding   Methane (CH4) — London dispersion forces Dimethyl ether (CH3OCH3) — dipole-dipole attractions Methanol (CH3OH) — hydrogen bonding Therefore, Methanol - CH3OH with H-Bonding have highest Boiling Point among the given chemical compounds.

Answer: A) Oxytocin Explanation: Oxytocin is a mamallian hormone and also acts as neuro transmitter in the brain.