91) Like snakes, many insects grow by throwing away their skin several times.
92) Volcanoes are formed where the plates in the earth's crust meet.
93) In the fetus, cartilage forms a temporary skeleton that will gradually be changed into bone.
94) Jet engines go to the opposite direction upon touch down.
95) In the fetus, cartilage forms a temporary skeleton that will gradually be changed into bone.
96) A nuclear power plant gives off less radiation than a granite structure of similar proposition.
97) Innovations in electronic equipment are usually less expensive the second or third year after they are introduced.
98) Vegetables are necessary component of a well balanced diet.
(A) a scarce
(B) an essential
(C) a pleasant
(D) an abundant
99) The discovery of penicillin by Alexander Flaming was an incidental part of another experiments.
(A) of secondary importance
(B) very large
(C) very helpful
(D) time consuming
100) Plastic has replaced many metals parts in new cars because it is lighter.
(A) not as rare
(B) not as costly
(C) not as heavy
(D) not as rigid