Answer:
Jose and Sarah are running in the cross country meet. Their skeletal and muscular systems work to move them through the course. As they run, they breathe faster and harder and their heart rate increases.
A.work together
Explanation:This should help:)
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Answer:
Most viscous to least viscous: 
Explanation:
For hydrocarbons, viscosity increases with increasing molar mass. Because increasing molar mass signifies increase in number of electrons in molecules.
We know that in non-polar hydrocarbons, only van der waal intermolecular force exists. Van der waal force is proportional to number of electrons in a molecule.
Therefore with increasing molar mass, van der waal force increases. hence molecules gets more tightly bind with each other resulting increase in viscosity.
Here molar mass order : 
Therefore viscosity order : 