(21)Which of the following is an iron ore ?
(a) Nitrite
(b) Lignite
(c) Magnetite
(d)Bauxite
(22)Which one of the following is an extinct animal ?
(a) Ibis
(b) Pink-headed duck
(c) Mountain quail
(d)Passenger pigeon
(23)From which one of the following is quinine extracted ?
(a) Datura
(b) Cinchona
(c) Opium
(d)Sarpagandha
(24) ‘Pigeon milk’ is produced by
(a) All of the above
(b) Mammals
(c) Birds
(d)Crop
(25)In which one of the following is swim bladder absent ?
(a) Silverfish
(b) Cartilaginous fish
(c) Bony fish
(d)Cuttlefish
(26)Magnifying Glass is
(a) Cylindrical lens
(b) Convex lens
(c) concave lens
(d)Plano-concave lens
(27)Water will not be vapourised if
(a) the temperature is 100 degree C
(b) the humidity is 100%
(c) the humidity is 0%
(d)the temperature is 0 degree C
(28)Which of the following is not a part of a CRT ?
(a) Gas plasma
(b) Electron gun
(c) Shadow mask
(d)Phosphor screen
(29)The pitch of sound depends on its
(a) Amplitude
(b) Velocity
(c) Intensity
(d)Frequency
(30)Which one of the following is an example of a gel ?
(a) Shaving cream
(b) Face cream
(c) Milk
(d)Cheese