doing a data analysis on the whole area gives us a number of outpoints.

How would the previous sentence be correctly capitalized?
Answer: Doing a data analysis on the whole area gives us a number of outpoints.
it was at this time that the student numbers reached a maximum, then they began to drop again.

How would the previous sentence be correctly capitalized?
Answer: It was at this time that the student numbers reached a maximum, then they began to drop again.
each of us is required to cooperate in, and maintain the confidentiality of, any such investigation.

How would the previous sentence be correctly capitalized?
Answer: Each of us is required to cooperate in, and maintain the confidentiality of, any such investigation.
can anyone live with such a lethal thought?

How would the previous sentence be correctly capitalized?
Answer: Can anyone live with such a lethal thought?