下列哪一种是常用的涂料填充料（）
A. 飞灰
B. 二碳酸钠
C. 滑石粉
D. 氢氧化钠
The notice of casualty to a ship must include（）.
A. a request for assistance
B. the location of the unit at the time of the casualty
C. an estimate of the cost to repair damages
D. the amount of fuel remaining
Second, the car needs（）collisions.
A. to be able to avoid
B. being able to avoid
C. to be able to avoiding
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