1126: Acid precipitation is now regarded as a serious problem in some European and Asian countries. Its major cause or source is
(a) discharge of acidic effluents onto neutral or slightly alkaline land where the acidic components precipitate
(b) emissions of sulphur oxides and nitrogen oxides from thermal power plants and burning of fossil fuels; these oxides dissolve in atmospheric water vapour and fall back on earth as acid rain
(c) natural carbon dioxide released during respiration of living organisms dissolves in water, forming carbonic acid which is the chief contributor to acidity in rain water
(d) chloro-fluoro-carbons readily react with various chemicals near the earth's surface, producing acidic intermediates which cause acid precipitation
1127: The average height of 2 students in a class is 115 cm. Ten more students with an average height of 130 cm join them. Therefore, the average height of the group of students now becomes:
(a) 110 cm
(b) 120 cm
(c) 130 cm
(d) 140 cm
1128: The half-life of a radio active element is 5 years. The fraction of the radioactive substance that remains after 20 years is
(a) 1/2
(b) 1/4
(c) 1/8
(d) 1/16
1129: Which one of the following pairs is not correctly matched ?
(a) Bakhti itihas : Badal Sarkar
(b) Sita Swayamvar : Vishnu Das Bhave
(c) Yayati : Girish Karnad
(d) Giddha : Jabbar Patel
1130: Match List I with List II and select the correct answer using the codes given below the Lists :
List I--------------------List II
(Volcanic Mountain)-----(Country)
I. Mt. Rainier------------(A) Italy
II. Etna-----------------(B) Mexico
III. Paricutin-------------(C) Philippines
IV. Taal------------------(D) USA
Codes:
(a) I-D, II-B, III-A, IV-C
(b) I-D, II-A, III-B, IV-C
(c) I-B, II-A, III-D, IV-C
(d) I-D, II-C, III-B, IV-A