{{B}}Dark Forces Dominate
Universe{{/B}} The Earth, moon, sun and all visible stars in the sky make up less than one per cent of the universe. Almost all the rest is dark matter and dark energy, unknown{{U}} (1) {{/U}}that puzzle astronomers. Observations in recent years have changed the basic understanding of how the universe evolved and have emphasized for astronomers how little is known{{U}} (2) {{/U}}the major forces and substances that shaped our world: Astronomers now know that luminous matter-stars, planets and hot gas — {{U}} (3) {{/U}}only about 0.4 per cent of the universe. Non. luminous components, such as black holes and intergalactic gas, make up 3.6 per cent. The rest is either dark matter, about 23 per cent, or dark energy, about 73 per cent. Dark matter, sometimes called "c A. universal B. additional C. fundamental D. structural [单选题]绝缘手套、绝缘靴的工频耐压试验周期为()。
A.三个月 B.一年 C.一年半 D.两年 E./ F./ [单项选择]在信息安全中,最活跃的因素是()。
A. 主机 B. 网络 C. 人 D. 信息 [单项选择]建筑在不避风的高地、河边、海岸、旷野上的建筑物以及城镇、厂区内特别高的建筑物,垂直的外围护结构风力附加率为()
A. 0~10% B. 5%~10% C. 5%~15% D. 10%~15% [单项选择]会议评估表格设计的质量将影响( )。
A. 参会者评估的兴趣 B. 讨论结论的质量 C. 反馈数据的质量 D. 会议总结的质量 [多选题]以下哪些卡可以透支使用一次,最大透支额为7元。()。
A.地铁普通储值卡 B.IC龙卡 C.智慧通·普通卡 D.民生银行卡 [单项选择]摄影涉及的学科不包括()
A. 光学 B. 美学 C. 心理学 D. 物理学 我来回答: 提交
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