(a) Company "X" produces 300 drums/week of color products under carefully controlled conditions as per quality assurance (QA) specifications and each drum is subjected to a precise color analysis test. Assume "A" is the number of bad drums produced per week. The company considers the process operation normal as long the number of bad drums produced in a week does not exceed FOUR standard deviations above the mean value for the base period. If "A" exceeds this value, the process is declared out of specification and production is suspended for routine maintenance. The QA test series data for a 12 week period are given in Table 1. Table 1: QA test series data Week 1 2 3 4 5 6 7 8 9 10 11 12 27 17 24 23 19 21 24 20 21 19 22 26 i) How many bad batches need to be produced for production to be shut down? (5 marks) ii) Give your comments on using this stricter criterion. (3 marks) (b) A mixture of propane (C3H8) and air containing 9.0 mole% C3H8 flowing on a rate of 700 kg/h needs to be diluted with pure air below the lower flammability limit. Assume the mixture can be ignited at a mole percentage of C3Hg between 6% and 15%. The molecular weight of C3Hg is 44.09 and average molecular weight of air is 29. i) Calculate the required molar flow rate of air. (5 marks) ii) Calculate the concentration of oxygen in percentage by mass in the product gas. (3 marks) (c) Explain FOUR (4) ways to measure the concentration of a solute in a solution. (4 marks)