What is the evidence that the appellant waived her right to remain silent in a police interview?

We note that appellant understandably was upset, had been drinking and had a history of emotional instability. Nevertheless, she was able to respond to the questions asked of her coherently. At one point, appellant told Sgt. Demkowski, "Now you can go on questioning me." Having reviewed the record we conclude that appellant knowingly and intelligently waived her right to remain silent. (Cf. People v. Barrow, supra, 60 Cal.App.3d 984, 991, 131 Cal.Rptr. 913; People v. Fisher (1975) 49 Cal.App.3d 174, 179, 122 Cal.Rptr. 366.)