按DIN规范,25mm钢板在RT时须达到2%之灵敏度,则像质计哪一条线应显示出来?()
A、0.3mm
B、0.4mm
C、0.5mm
D、0.6mm
参考答案:C
根据语篇情景,用恰当的短语或句子填空,使之意思完整。
Class Nine 1.________________________ on the school trip. They went to Blue Water Aquarium for the day. First they visited the Visitors’ Center and watched a movie about sharks. Then they watched a dolphin show. After that, they went to the Outdoor Pool and saw a big octopus. After lunch, they went to the Gift Shop and 2.____________________________. Finally, tired but happy, they took the bus back to school. At the end of the day, the science teacher 3. __________________ because the class monitor cleaned the bus after the trip.
怀特海说:科学研究的概率是999个想法会没有任何结果,可是,第1000个想法也许会改变世界。可见,好想法的产生不是________的。填入划横线部分最恰当的一项是()。
A.随心所欲
B.轻而轻举
C.一蹶而就
D.信手拈来