11. The word "durable"' in hue 3 is closest in meaning to
(A) lasting
(B) delicate
(C) heavy
(D) Plain
12. What does the author imply about the raw materials used to make glass?
(A) They were the same for centuries.
(B) They arc liquid
(C) They are transparent
(D) They are very heavy.
13. According to the passage, how is glass that has cooled and become rigid different from most other rigid substances?
(A) It has an interlocking crystal network.
(B) It has an unusually low melting temperature.
(C) It has varying physical properties.
(D) It has a random molecular structure.
14. The word "customarily" in line 13 is closest in meaning to
(A) naturally
(B) necessarily
(C) usually
(D) certainly
15. The words "exposed to" in line 19 are closest in meaning to
(A) hardened by
(B) chilled with
(C) subjected to
(D) deprived of
16. What must be done to release the internal stresses that build up in glass products during manufacture?
(A) the glass must be reheated and evenly cooled.
(B) the glass must be cooled quickly.
(C) The glass must be kept moist until cooled.
(D) The glass must be shaped to its desired form immediately
17. The word "induced" in line 21 is closest in meaning to
(A) joined
(B) missed
(C) caused
(D) lost
18. The word "it" in line 22 refers to
(A) feature
(B) glass
(C) manner
(D) viscosity
19. According to the passage. why can glass be more easily shaped into specific forms than can metals
(A)It resists breaking when heated
(B)It has better optical properties.
(C)It retains heat while its viscosity changes.
(D) It gradually becomes softer as its temperature rises.