Answer: A) +6 Explanation: In H2SO4, Hydrogen has a charge of +2, with each hydrogen has +1. Oxygen has  a charge of -8, with each oxugen has -2. Total charge = (2 - 8) = -6 Therefore, the Oxidation number of Sulphur S is '+6' because to make the compound stable.

Answer: A) History Explanation: Detailed description of a man's life is Biography. Similarly, detailed description of a Nations is called History.

Answer: B) 18.75% Explanation: Given that to find 15 of 80 => What % of 80 is 15 Let it be 'p' => p% of 80 = 15 => p x 80100 = 15⇒p = 15 x 10080⇒p = 150080 = 18.75   Therefore, 15 is 18.75% of 80 => 18.75% of 80 = 15   Example:: Now, in the similar way we can find 15% of 80 =? => 15x80/100 = p => p = 4 x 3 = 12   Therefore, 15% of 80 = 12

Answer: D) 4926@ Explanation: Pour - 4156 => P = 4,  r = 6 Sware - 78269 => a =  2,  e = 9 Clear - 3@926 => l = @ => Pearl = 4926@

Answer: A) Light Explanation: Light travels Faster than Sound.   Light : 1. Light doesn't require a medium to travel. 2. It travels in the vaccum with the speed of 1,86,000 miles per second.   Sound: 1. Sound rquire a medium. 2. It travels in the Air with the speed of 340 meters per second. 3. It travels Faster in Water than in Air. 4. It travels Faster in Steel than in Water.

Answer: A) The conference was only supposed to be an hour; however, it ran for nearly two and half hours. Explanation: The correct punctuated sentence is A The conference was only supposed to be an hour; however, it ran for nearly two and half hours.

Answer: A) TRUE Explanation: True, Air is a Mixture. Air is considered as mixture for the following reasons ; 1. Air can be separated into its components like N2, O2 , Argon and CO2 by the process of fractional distillation of liquid air. 2. Air shows the properties of all the gases present in the atmosphere. For example : Oxygen is good Supporter of combustion. Hence air also is good supporter of combustion. 3. Air does not have a fixed formula. 4. Air has a variable composition because air at different places contains different amount of gases. 5. Heat or Light energy is neither absorbed nor released when air is prepared physical by mixing required amount of gases . 6. Mixture does have fixed boiling Point. It holds good in case of liquid air.

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