(a) reduces evaporation of petrol
(b) increases efficiency of petrol
(c) prevents freezing of petrol
(d) reduces consumption of petrol
Ans: (c)
289. What is the main constituent of a Pearl? [CDS 2011]
(a) Calcium carbonate and magnesium corbonate
(b) Calcium sulphate only
(c) Calcium oxide and calcium sulphate
(d) Calcium carbonate only
Ans: (a)
290. From which one among the following water sources, the water is likely to be contaminated with fluoride? [CDS 2011]
(a) Groundwater
(b) River water
(c) Pond water
(d) Rain water
Ans: (a)
291. Which one among the following will you put into pure water in order to pass electric current through it? [CDS 2011]
(a) Kerosene
(b) Mustard oil
(c) Lemon Juice
(d) Sugar
Ans: (c)
292. Math the following: [CDS 2011]
Acid Source
A. Lactic acid 1. Tamarind
B. Tartaric acid 2. Orange
C. Oxalic acid 3. Tomato
D. Citric acid 4. Sour curd
A B C D
(a) 2 3 1 4
(b) 2 1 3 4
(c) 4 3 1 2
(d) 4 1 3 2
Ans: (d)
293. Cutting and peeling of onions brings tears to the eyes because of the presence of [CDS 2011]
(a) sulfur in the cell
(b) carbon in the cell
(c) fat in the cell
(d) aminoacid in the cell
Ans: (a)
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