Final answer:
The total volume of the dilution is the sum of the volumes of the patient's serum and the diluent, resulting in 20mL. The correct answer is 1) 20mL.
Step-by-step explanation:
The question asks us to determine the total volume of a dilution made by mixing 2mL of a patient's serum with 18mL of diluent. To find this, we simply add the volume of the serum (2mL) to the volume of the diluent (18mL).
Total volume = Volume of serum + Volume of diluent
Total volume = 2mL + 18mL
Total volume = 20mL
Therefore, the correct answer is 1) 20mL.