题干

“雪碧”是一种无色的碳酸饮料,将少量“雪碧”滴入紫色石蕊试液中,然后再加热,溶液的颜色变化情况是( )

A:先变红后变紫

B:变红后颜色不再改变

C:先变无色后变红

D:先变蓝后变紫

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答案(点此获取答案解析)

A

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    Driverless technology will soon enter another major global industry: shipping. Several companies recently announced plans to start self-sailing ships to improve safety and efficiency(效率).

    One of them is Norwegian chemical company Yara International. Yara has designed to build an autonomous ship expected to start next year. The ship is fully electric to reduce air pollution. It is designed to carry containers normally transported by truck. This means the ship will also improve road safety by replacing about 40,000 truck trips a year.

    Yara plans to operate the ships by remote control beginning sometime next year. By 2020, the ships should be loading and sailing themselves. Another company focusing on self-sailing ships is the world's largest mining company, Australia's BHP Billiton. The company's Vice President of Freight, Rashpal Bhatti, recently spoke about the technology. He said, “I believe automation(自动化)will be one of the biggest changes for shipping in the future.” Autonomous ships offer important chances to improve safety and provide better efficiency results to the marine supply chain. He added that self-sailing ships could become a reality within the next decade.

    Rolls-Royce, the British automobile and engine manufacturer, is also developing unmanned shipping technologies. Oskar Levander is the company's head of marine operations. He told a conference last year, “This is happening. It's not if, it's when.” Several shipping companies have invested hundreds of millions of dollars to develop self-sailing ships expected to be used by 2025. These ships will be equipped with technology to collect weather and sea data. They will then use the data to plan out the safest, shortest and most fuel-efficient route.