“2015IOAA理论短问题第7题-星团密度”的版本间的差异
来自astro-init
（创建页面，内容为“==英文题目== A galaxy at the boundary of a galaxy cluster of radius 10 Mpc is expected to escape from the cluster if it has an initial velocity of at least 700 k…”） |
（没有差异）
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2022年3月18日 (五) 20:30的最新版本
英文题目
A galaxy at the boundary of a galaxy cluster of radius 10 Mpc is expected to escape from the cluster if it has an initial velocity of at least 700 km/s relative to the center of the cluster. Calculate the density of the cluster.
