1496: Which one of the following was used as a chemical weapon in the First World War?
(a) Carbon monoxide
(b) Hydrogen cyanide
(c) Mustard gas
(d) Water gas
1497: Which feature of some, species of blue-green algae helps promote them as bio-fertilizers?
(a) They convert atmospheric methane into ammonia which the crop plants can absorb readily
(b) The induce the crop plants to produce the enzymes which help convert atmospheric nitrogen to nitrates
(c) They have the mechanism to convert atmospheric nitrogen into a form that crop can absorb readily
(d) The induce the roots of the crop plants to absorb the soil nitrates in larger quantities
1498: Lead, ingested or inhaled, is a health hazard. After the addition of lead to petrol has been banned, what still are the sources of lead poisoning?
1. Smelting units
2. Pens and pencils
3. Paints
4. Hair oils and cosmetics
Select the correct answer using the codes given below :
(a) 1, 2 and 3 only
(b) 1 and 3 only
(c) 2 and 4 only
(d) 1, 2, 3 and 4
1499: The river most mentioned in early Vedic literature is
(a) Sindhu
(b) Sutudri
(c) Sarasvati
(d) Ganga
1500: Consider the following countries of South Asia
(a) Bangladesh
(b) India
(c) Pakistan
(d) Sri Lanka
The descending order of literacy status of these countries is
(a) 4, 2, 1, 3
(b) 2, 4, 3, 1
(c) 4, 2, 3, 1
(d) 2, 4, 1, 3