11. Which of the following is not a ‘Greenhouse gas’?
(A) Nitrous oxide
(B) Carbon dioxide
(C) Methane
(D) Nitrogen
Block Extension Educator (BEE) (Dec 2020 & 2021)
12. Which one of the following pairs of animals is warm blooded?
(A) Crocodile and Ostrich
(B) Hagfish and Dogfish
(C) Tortoise and Ostrich
(D) Peacock and Camel
Block Extension Educator (BEE) (Dec 2020 & 2021)
13. The gas usually filled in the electric bulb is
(A) Nitrogen
(B) Hydrogen
(C) Carbon dioxide
(D) Oxygen
CDPO 2023
14. Quartz crystals normally used in quartz clocks etc. is chemically
(A) Silicon dioxide
(B) Germanium oxide
(C) A mixture of germanium oxide and silicon dioxide
(D) Sodium silicate
CDPO 2023
15. Very small time intervals are accurately measured by
(A) White dwarfs
(B) Quartz clocks
(C) Atomic clocks
(D) Pulsars
CDPO 2023
16. Which among the following is a positively charged particle emitted by a radioactive element?
(A) Beta ray
(B) Alpha ray
(C) Cathode ray
(D) Gamma ray
CDPO 2023
17. Detergents used for cleaning clothes and utensils contain?
(A) Bicarbonates
(B) Bismuthates
(C) Sulphonates
(D) Nitrates
CDPO 2023
18. The blackboard seems black because it
(A) reflects every colour
(B) does not reflect any colour
(C) absorbs black colour
(D) reflects black colour
CDPO 2023
19. Which one among the following is the main ingredient in cement?
(A) Gypsum
(B) Limestone
(C) Clay
(D) Ash
CDPO 2023
20. If there is no Sun, the colour of the sky would be
(A) orange
(B) yellow
(C) blue
(D) black
CDPO 2023