Final answer:
The question appears to refer to diastolic blood pressure, with normal measurements falling between 60 to 110 mm Hg, and a desirable level below 80 mm Hg.
Step-by-step explanation:
The normal main reservoir pressure that the student is asking about seems to be referencing blood pressure measurements. These measurements typically fall within the range of 20-114 lbs (which is pounds per square inch or psi). However, the pressure in the circulatory system is minimum at the point called diastolic pressure, which can range from 60 to 110 mm Hg, with a desirable diastolic pressure being less than 80 mm Hg. While the question appears to be referring to a general pressure reservoir, it's important to clarify that in terms of human physiology, diastolic blood pressure is the relevant term and measurement range.
In the circulatory system, the normal main reservoir pressure is in the range of 20-114 lbs. However, when measuring blood pressure, it is typically expressed in millimeters of mercury (mm Hg) rather than pounds. The desirable diastolic pressure is less than 80 mm Hg.