dm. Designated Marksman. military marksman role in a U.S. infantry squad. The DM's role is to supply rapid accurate fire on enemy targets at ranges up to 870 yds with a highly-accurate semi-automatic rifle equipped with a telescopic sight.he DM's role is to supply rapid accurate fire on enemy targets at ranges up to 870 yds with a highly-accurate semi-automatic rifle equipped with a telescopic sight.
The average person is awake for about 14 to 16 hours per day. Most could extend that to about 20 hours if they were to stay up later; up to 40 hours is easy once a person gets beyond the 24 hour mark; longer than 60 hours (staying awake straight through two nights and three days) is rare, but doable; the record is 264 hours or 11 days straight. Hannah Griffiths.
The easy experimental answer to this question is 264 hours (about 11 days). In 1965, Randy Gardner, a 17-year-old high school student, set this apparent world-record for a science fair. Several other normal research subjects have remained awake for eight to 10 days in carefully monitored experiments.