Answer:
It encourages the growth of a group of certain bacteria while inhibiting the growth of others. It contains a high concentration (~7.5%-10%) of salt (NaCl), making it selective for gram positive bacteria Staphylococci (and Micrococcaceae) since this level of NaCl is inhibitory to most other bacteria.
Explanation:
Answer:
Maybe it is 5.50 because not much information is given to calculate it or to find it.