[单选题]参加地震、地质、气象等自然灾害救援时，应配备护膝、护肘、防尘口罩等防护装备，必要时携带[]小时个人保障物资。
A.24
B.36
C.48
D.72

In general, the ancient Romans were a practical people. They cared less about philosophy anti pure mathematics than did the Greeks. The Romans were the best of the ancient engineers anti architects. They were brilliant students of Greek geometry and trigonometry, and they applied their knowledge to the constructions of fine bridges, roads, aqueducts, and public buildings.
They knew about the smelting of iron ore, but they used the iron they produced mainly for spears, swords, and shields, rather than for building construction.
While the Romans accomplished practical wonders, they did very little theoretical scientific thinking. Because of their frequent wars, many of their inventions were no more than improvements in the design of Greek weapons with which they were familiar.
There are two reasons for the Romans neglect of philosophy and pure mathematics. First, they were apparently too busy conquering nearby nations and forming them into a rapidly
A. They learned Greek geometry and trigonometry.
B. They made Greek spears, swords, and shields.
C. They were involved in frequent wars.
D. They employed Greek engineers.