题干

下列是一些日常生活和自然界中的光现象:①日食和月食;②水中倒影;③小孔成像;④池底“变浅”;⑤黑板“反光”;⑥雨后彩虹.由于光的直线传播形成的是:____; 由于光的反射形成的是:____.(选填序号)

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①③,②⑤

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    In 1970, a cyclone(旋风) hit the southern coast of Bangladesh(孟加拉国). So severe and deadly were its effects that it's1listed as the world's worst-ever reported natural disaster. The2had a big impact on two Swedish men from Mission Aviation Fellowship(MAF). They traveled 3to Bangladesh for the purpose of seeing what they could do to4. They journeyed south by boat for several days, throughout the country's vast 5 network to reach the worst-affected area and began to envision(预想) MAF using an aircraft that would 6direct access to large areas of the country that were almost out of7.

    Throughout the 1980s, MAF Australia, along with other MAF groups, sent staff to8assistance and their patience and dedication 9since they built trust in the countries that had been 10.

    In 1997, MAF could11start a flight program within Bangladesh. At that time, besides transporting doctors to hospitals located in 12parts of the country, MAF also 13an on-call emergency medevac(前线急救直升机) service in Bangladesh.

    On November 15, 2007, Cyclone Sidr hit southern Bangladesh. MAF's14response and emergency procedures were seriously15as the office received over 200 phone calls in one day from aid agency personnel in urgent need of 16to and from the disaster zone. For the next two months, MAF17solidly, seven days a week. The float plane became known by18locals as “The Sea Angel(天使)”—the only aircraft in the country of its type having such a(n) 19.

    In 2009, “The Sea Angel” was sent again for rapid assistance20Cyclone Alla struck. Today, in Bangladesh, MAF makes over 750 flights and transports around 2,500 passengers annually.