2. For a certain type of metal alloy, two separate hardening processes are used: saltwater quenching and oil quenching. The following table summarises the findings. Saltwater 152 150 147 155 1411 145 153 152 151 143 155 011 145 150 153 143 141 152 145 154 143 143' Assume the distribution of hardness is normal. i. ii. Calculate a 95% condence interval on the ratio of variances for the two separate hardening processes. Thus, can you conclude that the variabilities of the two pro- cesses are equal? Justify your answer. (7 marks) Using the results in part (i), construct a 98% condence interval on the diEerence in means between the hardness for the saltwater quenching process and oil quenching process