What is the first step in the dilution of stock solutions?

a. ensure that all numbers are rounded off to the nearest decimal for easier calculation.
b. ensure that percentage strengths are converted to ratio strengths.
c. keep proportions at the highest terms.
d. make sure that ratio strengths are converted to percentage strengths.

A92-year-old man with a 45-year history of chronic obstructive pulmonary disease is intubated in the icu because of a bout of viral pneumonia that fails to improve after 72 hours of antibiotics. although the inspired fraction of oxygen is 100%, the patient's po2 remains at 57 mmhg. positive-end expiratory pressure (peep) is added to allow the inspired fraction of oxygen. twelve hours after the introduction of peep the patient suddenly become hypotensive. at the same time, his oxygen saturation drops from 92% to 61%. on physical examination, his bp is 80/50 mmhg and his pulse is 124/min. he has distended neck veins and distant heart sounds. which of the following would also most likely be seen on this patient's physical examination? - absence of breath sounds in the right hemithorax- high amplitude carotid artery upstroke- a pleural friction rub- pulsus alternans- splenomegaly

When a researcher debriefs her participants, she: provides a detailed explanation of the study. removes their undergarments. tells them they can stop taking part at any time. provides an detailed explanation of the study, and tells them they can stop taking part at any time.

Which of these statements describes clinical depression? a. a milder form of depression that usually follows a traumatic event b. a medical condition that may occur due to a chemical imbalance in the brain c. alternate feelings of extreme happiness and extreme sadness