Help with calculating a .386 DUI

My friend (and actually my friend because I am obviously not in jail) blew a .386 after killing a woman at 10am. She says her last drink was 1:30am. I know that is not physically possible. Can someone piece together to me how much she must have drank to blow a .386 at 10am? I am assuming she started drinking around midnight. She is 5’4 and 170 pounds.