Mr  Wu, Mr  Zhang, Mr  Sun and Mr  Su are all teachers in a certain school, each teaching only one course in Chinese, biology, physics and chemistry  It is known that: 1  If Mr  Wu teaches Chinese, then Mr  Zhang does not teach biology   2  Or Mr  Sun teaches Chinese, or Mr  Wu teaches Chinese  3  If Mr  Zhang does not teach biology, then Mr  Su does not teach physics  4 Or Mr  Wu does not teach chemistry, or Mr
Su teaches physics
Mr. Wu teaches chemistry