Answer:What is the question
Explanation:
Answer:
More oxygen is needed to produce more energy, and more carbon dioxide waste must be removed from the body.
Explanation:
Oxygen helps our cells work harder by breaking down the nutrients we get from food like sugars. With sugars and oxygen, our cells can create the energy they need to function. This process also produces carbon dioxide. The carbon dioxide produced is a waste product and needs to be removed. During exercise, your body needs more energy, which means your tissues consume more oxygen than they do at rest. Consuming more oxygen means you will also produce more carbon dioxide because your metabolic rate is elevated. The lungs and respiratory system allow oxygen in the air to be taken into the body, while also letting the body get rid of carbon dioxide in the air breathed out. When you breathe in, the diaphragm moves downward toward the abdomen, and the rib muscles pull the ribs upward and outward.
Answer:
60%
Explanation:
M(NH4NO3) = 2*14 +4*1 +3*16 = 80 g/mol
M(3O) = 3*16 = 48 g/mol
(48/80) *100 % =60% oxygen by mass.
Answer:
c. Cr
Explanation:
The compound is containing 
ion.
If acid reacts with it, CO_2 evolves.
therefore, Cr would form a precipitate when added to an aqueous solution of this compound. Cr2CO3 is the precipitate.
