45. ___
A. The lights attract predators.
B. They need to save electricity.
C. The baby turtles are attracted to light.
D. The volunteers use lights for signals.
46. ___
A. Write a report about their activities.
B. Attend make-up classes with Dr. Webster.
C. Help find turtle eggs before they hatch.
D. Spend two hours working for the project.
47. ___
A. How people in rural areas preserved food.
B. The construction of icehouses.
C. An important industry in the nineteenth century.
D. How improvements in transportation affected industry.
48. ___
A. Modem technology for the kitchen.
B. Improved transportation systems.
C. Industrial use of streams and rivers.
D. Increased temperatures in many areas.
49. ___
A. Only wealthy families had them.
B. They were important to the ice industry.
C. They were built mostly on the east coast.
D. They are no longer in common use.
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