She bakes a turkey for 15 minutes a pound and the turkey is 16 pounds so it takes 15*16 = <<15*16=240>>240 minutes
She has 2 turkeys to roast and one turkey takes 240 minutes to cook so 2 turkeys will take 2*240 = <<2*240=480>>480 minutes
There are 60 minutes in an hour and these turkeys will take 480 minutes to cook so that's 480/60 = <<480/60=8>>8 hours
In military time, 6:00 pm is 18:00 hours (12 hours +6 hours) and it takes 8 hours to cook the turkeys so the latest she can start is 18- 8 = 10:00 am
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