46: Which of the following crops has the highest photosynthetic activity?
(a) Cotton
(b) Sugarcane
(c) Rice
(d) Wheat
47: In India, cluster bean (Guar) is traditionally used as a vegetable or animal feed, but recently the cultivation of this has assumed significance.
Which one of the following statements is correct in this context ?
(a) The oil extracted from seeds is used in the manufacture of biodegradable plastics
(b) The gun made from its seeds is used in the extraction of shale gas
(c) The leaf extract of this plant has the properties of anti-histamines
(d) It is a source of high quality biodiesel
48: Consider the following chemicals :
1. Benzene
2. Carbon tetrachloride
3. Sodium Carbonate
4. Trichloroethylene
Which of the above is/are used as dry cleaning chemicals ?
(a) 1 Only
(b) 2 Only
(c) 1, 2 and 4 Only
(d) 1, 2, 3 and 4
49: Diffusion of light in the atmosphere takes place due to
(a) Carbon dioxide
(b) Dust particles
(c) Helium
(d) Water vapours
Explanation:
Diffusion of light in the atmosphere takes place due to dust particles.
50: Match List I with List II and select the correct answer using the codes given below the Lists :
List I-------------------List II
I. German Silver---------(A) Tin
II. Solder----------------(B) Nickel
III. Bleaching Powder-----(C) Sodium
IV. Hypo-----------------(D) Chlorine
Codes:
(a) I-A, II-B, III-D, IV-C
(b) I-B, II-A, III-C, IV-D
(c) I-A, II-B, III-C, IV-D
(d) I-B, II-A, III-D, IV-C