[单选题]电动工具的电气部分经维修后，应进行绝缘电阻测量及绝缘耐压试验，试验时间为（　　)。
A.15s
B.30s
C.1min
D.2min

{{B}}The Mir Space Station{{/B}}
The Russian ’Mir Space Station, which came down in 2001 at last after 15 years of pioneering the concept of long-term human space flight, is remembered for its accomplishments in the human space flight history. It can be credited with many firsts in space.
During Mir’s lifetime, Russia spent about USS 4.2 billion to build and maintain the station.
The Soviet Union launched Mir, which was designed to last from three to five years, on February 20, 1986, and housed 104 astronauts over 12 years and seven months, most of whorh were not Russian. In fact, it became the first international space station by playing host to 62 people from 11 countries. From 1995 through 1998, seven astronauts from the United States took turns living on Mir for up to six months