Huy?n tho?i tennis Roger Federer và bà xã Mirka h?i ng? v? ch?ng ??ng nghi?p n? m?t th?i Ana Ivanovic t?i l? trao gi?i ?i?n ?nh Oscar t?i 10/3.Harmonics are periodic distortions of voltage, latest, or ability sine waves. Harmonics in ability distribution programs are sometimes caused by non-linear masses for example switched mode dc electricity