Does size matter? (please gimme your opinion)

How do astronomers measure the amount of dark matter in the universe

98 points! include an answer and in advance!

Imagine a 28-year-old man named keith is about to be released from prison after serving a seven year sentence. keith is not sure where to start when he gets out. the lease on his apartment and his job are both long gone. he has no immediate family to get him a hand, he will be completely on his own. what types of things do you think he might need with once he is released?