. Chemists use pH to measure the acidlalkaline nature of compounds. A large vat of mixed commercial chemicals is supposed to have a mean pH p = 6.4 with a standard deviation 0 = 1.7 pH. Assume a normal distribution for pH values. If a random sample of 10 readings in the vat is taken and the mean pH is computed. What is the probability that the mean pH 3? for these readings is: a. H; = o; = (round standard deviation to the nearest hundredth) b. P072 5) = P( )= C. P(YS 7)=P( )= d. P(55757)=P( )=