What is the pH of a 0.028M solution (pH=-log(M))

A) 3.56
B)2.88
C)1.55
D)1

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.