At the trial of a woman for killing a man in her home, where there was evidence that during an argument between them the victim, who had beaten her on previous occasions, threatened her, that she then ran downstairs to a basement playroom where her children were, that the victim at first threatened to go down and kill her and the children and then said he would leave the house, but instead returned to the top of the stairs and went down a few steps, whereupon the defendant, without warning the victim, fired one fatal shot at him from a rifle which she had taken from a rack on the wall and loaded, that more than five minutes elapsed between the time she went to the basement and the shooting, and that she had ample opportunity to call the police and to leave the basement with the children, there was no error in instructions to the jury that the defendant, in order to establish that she used deadly force in self-defense, must have had a reasonable apprehension of fatal or serious harm to herself or her children at the hands of the victim and must have "endeavored to avoid any further struggle and retreated as far as she could until there was no probable means of escape," and that the jury must consider all the circumstances relevant to the issue of self-defense, including the fact that the occurrence was in the defendant's own home "where she had a right to be" and "the means of escape from the basement"; this court declined to apply a rule that one assaulted in his own home need not retreat before resorting to the use of deadly force.