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.
Numerous other, less credible accounts abound, including one of a British woman in 1977 who won a competition to continuously rock in a rocking chair (presumably by a landslide) by doing so for 18 days. Overall, the jury is out on just how long a human could ever stay awake, but perhaps that's a good thing. Acknowledging the injury people might cause to themselves through intentional sleep deprivation, the Guinness Book of Records stopped keeping track of this particular superlative last decade.