21. Students entering the design competition have to
A. produce an energy-efficient design.
B. adapt an existing energy-saving appliance.
C. develop a new use for current technology.
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11&12. Which TWO facilities at the leisure club have recently been improved?
A. the gym
B. the tracks
C. the indoor pool
D. the outdoor pool
E. the sports training for children
26. Salvinia molesta plagues
A forage grass
B rice fields
C coconut trees
D fruit trees
E water hyacinth
F parthenium weed
G Brazilian beetles
H grass-scale insects
I larval parasites
25. An Argentinian weevil may be successful in wiping out
A forage grass
B rice fields
C coconut trees
D fruit trees
E water hyacinth
F parthenium weed
G Brazilian beetles
H grass-scale insects
I larval parasites
24. Leaf-mining hispides blighted
A forage grass
B rice fields
C coconut trees
D fruit trees
E water hyacinth
F parthenium weed
G Brazilian beetles
H grass-scale insects
I larval parasites
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