When Gypsum Is Mixed by Hand, the Mass Is Stirred

question 6

Multiple Choice

When gypsum is mixed by hand, the mass is stirred with a spatula at a rate of about _____ revolution(s) per second for _________.

• A) five; about 5 minutes
• B) two; about 2 minutes
• C) two; about 1 minute
• D) one; about 2 minutes
• E) one; 30 seconds

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Definitions:

Kidney Dialysis

A medical treatment for removing waste and excess water from the blood, acting as an artificial replacement for lost kidney function.

Active Transport

Use of a plasma membrane carrier protein to move a molecule or ion from a region of lower concentration to one of higher concentration; it opposes equilibrium and requires energy.

Diffusion

Movement of molecules or ions from a region of higher to lower concentration; it requires no energy and tends to lead to an equal distribution (equilibrium).

Urinary System

Organ system of humans that includes the kidneys, urinary bladder, and associated structures; excretes metabolic wastes; maintains fluid balance; helps control pH.