a) For the treatment of superficial skin infections, solutions which should consist of 1000 units of sodium penicillin per ml in sterile water were bottled. The penicillin content of a sample of 200 bottles was analysed and the following frequency table obtained. Penicillin (units) frequency 880-909 10 910-939 16 940-969 45 970-999 52 1000-1029 31 1030-1059 25 1060-1089 15 1090-1119 6 i) Construct a cumulative frequency curve and from it estimate the median. b) Solve the following equation for x, correct to four significant figures: 4.5^(3x)=248