A food scientist wants to study whether quality differences exist between yogurt made from skim milk with and without the preculture of a particular type of bacteria, called Psychrotrops (PC). Samples of skim milk are procured from seven dairy farms. One-half of the milk sampled from each farm is inoculated with PC, and the other half is not. After the yogurt is made with these milk samples, the firmness of the curd is measured, and those measurements are given below.

Curd Firmness A B C D. E F G

With PC 68 75 62 86 52. 46 72

Without PC 61 69 64 76 52 38. 68

Do these data substantiate the conjecture that the treatment of PC results in a higher degree of curb firmness?

Perform the appropriate hypothesis test showing all the necessary steps using the p-value approach and a level of significance of 5%