Which of these equations is balanced? a. h2o+co > h2co3 b. 2nacl +h2so4 > na2so4 + 2hcl c. 2cao+ h2o > ca(oh)2 d. mn +fe > mns + fe

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.