208 -The passage states that ----- .
A) most of the agricultural crops produced in the USA are lost to pests
B) caterpillars can help plants attacked by black wasps
C) scientists have known all about plants' distress calls for years
D) friendly insects can help plants against unfriendly ones
E) researchers have only recently become aware of the distress calls of plants
209 -According to the passage, further research into the plants' distress calls is necessary in
order for scientists ----
A) to act promptly when plants need help
B) to develop new chemicals to be used against pests
C) to understand whether plants really have this ability
D) to distinguish between useful and harmful insects
E) to make use of them in the fight against pests
210 -One can understand from the passage that "pest" means a ---- .
A) microscopic ambulance
B) specific signal
C) harmful insect
D) type of researcher
E) helpful insect
Not so long ago, most companies were family affairs, owned by different members of the same
family. Some still are, but now many companies have survived the founding families and grown into
big organisations which own smaller, or subsidiary companies. These companies work in other
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