Answer: D) All the above Explanation: A pure substance can be defined as any single type of material that has not been contaminated by another substance. In chemistry, a pure substance has a definite composition. It can be a compound or an element. A pure substance is considered to be a material that consists of one type of "building block" of matter. Examples of pure substances include tin, sulfur, diamond, water, pure sugar (sucrose), table salt (sodium chloride) and baking soda (sodium bicarbonate). Tin, sulfur, and diamond are examples of pure substances which are chemical elements. All elements are pure substances. Water, sugar, salt and baking soda are pure substances which are chemical compounds. Chemical compounds also are pure substances

Answer: B) 4 yrs Explanation: Let the present age of Deepa = 5p Let the present age of Hyma = 6p After four years their ratio = 6 : 7 => 5p + 46p + 4 = 67 => 35p + 28 = 36p + 24 => p = 4 Therefore, the difference between their ages = 24 - 20 = 4 years.

Answer: C) 2.83 kmph Explanation: Given speed of the person = 8 1/2 = 17/2 kmphLet the speed of the stream = x kmphspeed of upstream = 17/2 - xspeed of downstream = 17/2 + xBut given that,2(17/2 - x) = 17/2 + x=> 3x = 17/2=> x = 2.83 kmph.

The qualities that a person need, to be independent are: - Have a mind of your own.- Have the confidence to challenge accepted wisdom when required.- Can effectively work alone when necessary.

When the FTC was created in 1914, its purpose was to monitor all business practices to prevent unfair methods of competition in commerce as part of the battle to "bust the trusts."   Over the years, Congress passed additional laws giving the agency greater authority to police anticompetitive practices.

Answer: D) 51% Explanation:

Answer: B) FALSE Explanation: No, the given statement is False. Parasites are organisms that feed on other organisms causing harm to them. Foods that allow micro organisms to grow are called Growth Mediums.

Answer: D) 60/11 Explanation: A can complete the work in 12 days working 8 hours a day => Number of hours A can complete the work = 12×8 = 96 hours  => Work done by A in 1 hour = 1/96   B can complete the work in 8 days working 10 hours a day => Number of hours B can complete the work = 8×10 = 80 hours  => Work done by B in 1 hour = 1/80   Work done by A and B in 1 hour = 1/96 + 1/80 = 11/480  => A and B can complete the work in 480/11 hours   A and B works 8 hours a day. Hence total days to complete the work with A and B working together  = (480/11)/ (8) = 60/11 days