1311: A person starts from a point A and travels 3 km eastwards to B and then turns left and travels thrice that distance to reach C. He again turns left and travels five times the distance he covered between A and B and reaches his destination D. The shortest distance between the starting point and destination is
(a) 18 km
(b) 16 km
(c) 15 km
(d) 12 km
1312: The most reactive among the halogens is
(a) fluorine
(b) chlorine
(c) bromine
(d) iodine
1313: Barium in a suitable form is administered to patients before an X-ray examination of the stomach, because
(a) barium allows X-rays to pass through the stomach on account of its transparency to X-rays
(b) barium compound, like magnesium sulphate helps in cleaning the stomach before X-ray examination
(c) barium is a good absorber of X-rays and this helps the stomach to appear clearly in contrast with the other regions in the picture
(d) barium salts are white in colour and this helps the stomach to appear clearly in contrast with other regions in the picture
1314: With reference to the river Luni, which one of the following statements is correct?
(a) It flows into Gulf of Khambhat
(b) It flows into Gulf of Kuchchh
(c) It flows into Pakistan and merges with a tributary of Indus
(d) It is lost in the marshy land of the Rann of Kuchchh
1315: Consider the following statements:
1. The albedo of an object determines its visual brightness when viewed with reflected light.
2. The albedo of Mercury is much greater than the albedo of the Earth.
Which of the statements given above is/ are correct?
(a) Neither 1 nor 2
(b) Both 1 and 2
(c) 2 only
(d) 1 only