Everyday Science Mcqs

Stethoscope was invented by _______ ?

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Stethoscope was invented by _______ ?

A. Rene Laennec
B. Steven Sasson
C. Martin Cooper
D. Dave Hyatt

 
The stethoscope was invented in France in 1816 by René Laennec at the Necker-Enfants Malades Hospital in Paris. It consisted of a wooden tube and was monaural. Laennec invented the stethoscope because he was not comfortable placing his ear directly onto a woman’s chest to listen to her heart.

What is the third most common gas found in the air we breathe ________ ?

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What is the third most common gas found in the air we breathe ________ ?

A. Hydrogen
B. Neon
C. Carbondioxide
D. Argon

 
The most common gas people breathe from clean air is nitrogen. Air is a mixture of gases, and the air on Earth contains about 78 percent nitrogen and about 21 percent oxygen. Argon, carbon dioxide neon, helium, methane, krypton, hydrogen and xenon are in much smaller amounts.