676: Which of the following pairs is correct?
City : River
(a) Baghdad : Tigris
(b) Bonn : Danube
(c) Rome : Seine
(d) Paris : Tiber
677: Which one of the following countries is the leading producer of uranium?
(a) United States of America
(b) Zambia
(c) Canada
(d) Germany
678: Which of the following pairs is/are correctly matched ?
Inventor : Invention
1. Christopher : Hovercraft Cockerell
2. David Bushnell : Submarine
3. J.C. Perrier : Steamship
Select the correct answer using the code given below :
(a) 1 and 2, only
(b) 2 and 3, only
(c) 1 and 3, only
(d) 1, 2 and 3
679: Ice cubes are floating in a glass of water. When the ice cubes melt, the water level in the glass:
(a) Will first increase and then start decreasing
(b) Will first decrease and then start increasing
(c) Will remain unchanged
(d) Will increase
680: Chemical composition of pearl is:
(a) Calcium carbonate
(b) Calcium carbonate and magnesium carbonate
(c) Calcium sulphate
(d) Calcium chloride