11- ………………gas in water is very important for the survival of animals and plants.
(A) Chlorofluorocarbon
(B) Photosynthesis
(C) Hydrogen
(D) Oxygen
12- Those substances or materials through which object/things can be seen clearly are called ……………………
(A) none of the below
(B) translucent
(C) opaque
(D) transparent
13- Which of these is/are an example/s of transparent substances?
(A) glass
(B) water
(C) air
(D) all of the above
14- The material through which things cannot be seen?
(A) transparent
(B) opaque
(C) translucent
(D) none of the above
15- Which of these is/are an example/s of Opaque materials?
(A) wood
(B) cardboard
(C) metal
(D) all of the above
16- The materials through which objects can be seen but not clearly are known as ………………..
(A) Opaque
(B) Transparency
(C) Translucent
(D) All of the above
17- Stone is transparent, while glass is opaque. It is False statement or True
(A) False
(B) True
18- A notebook has luster while eraser does not . It is False statement or True
(A) True
(B) False
19- Chalk dissolves in water
(A) False
(B) True
20- A piece of wood floats on water. It is True or False
(A) False
(B) True
ANSWERS:
11-(D), 12-(D), 13-(D), 14-(B), 15-(D), 16-(C), 17-(A), 18-(B), 19-(A), 20-(B)