Final answer:
The normal PCV range for a cow is 30-40%. Human hematocrit values, which are similar to PCV, range from 36-50%, depending on gender. A hematocrit of 42% suggests a plasma percentage of 58% in humans.
Step-by-step explanation:
The normal range of packed cell volume (PCV) for a cow is B) 30-40%. This measure indicates the proportion of blood that consists of erythrocytes, or red blood cells. In humans, normal hematocrit values (which approximate PCV) range from 36 to 50 percent, varying by gender and other factors, with females typically ranging from 37 to 47 percent and males from 42-52 percent. However, these human reference values differ from those of cows. For a patient with a hematocrit of 42 percent, approximately 58 percent of their blood would be plasma, as plasma percentage is calculated by subtracting the hematocrit value from 100.