In National Museum of Natural History in Washington, D.C., visitors have a rare chance to enjoy a world filled with hundreds of living butterflies. It’s an e  小题1: exhibition.

It p 小题2:a close look at butterflies. Dan Babbitt,  one of the l 小题3: of the museum says visitors can get very close to the butterflies to learn about their i小题4:   .“Our purpose is to c小题5:  people to the natural world. We have found that using animals and insects is an amazing way to do that.” Babbitt says butterflies are important to the e  小题6: for several reasons.

“One big reason is because of pollination（授粉）. They will t 小题7:   from flower to flower, taking pollen(花粉) from one flower to another. So we won’t have a number of fruit that we like to eat w  小题8: butterflies.”

“We have butterflies from all over the world” he says. “And have already s 小题9:  about 5,000 or so different kinds.” He a  小题10:  that the museum’s goal for the next five years is to let more people learn more about butterflies .

海道测量的平面基准通常采用（）

A.1954北京坐标系

B.1980西安坐标系

C2000国家大地坐标系

D.WGS-84坐标系