Cell, tissue, organ, organ sytem, organism, population, community, ecosystem, biome.
Answer:
1. The respiratory system functions when our involuntary nervous system sends impulses to the muscles in the diaphragm; thereby, causing the lungs to expand and contract.
2. The respiratory system oxygenates the blood which is vital for bodily function as oxygenated blood is carried from your lungs to the left side of your heart, to be circulated throughout the body. Furthermore deoxygenated blood is carried back to the right side of your heart to get oxygenated once more.
3. The other body systems that are crucial for the lungs to function are the nervous system and the muscular system.
4. without the raspatory system the body wouldn't receive any oxygen and the brain would slowly die. therefore, without the brain the heart would stop functioning and atrophy etc.
Explanation:
Answer: 4
The mechanical advantage is the ratio of the force exerted by the object to the force applied to do work on it.
Here, Jeff tried to lift a rock weighing 600 pounds by wedging board under the rock. Jeff who weighs 150 pounds uses all his weight to exert force on lever and lift rock.
Mechanical advantage, 
Therefore, the mechanical advantage that lever provided to Jeff in lifting rock is 4.
Put the object or material on a scale to figure out<span> its mass. 3. Divide the mass by the volume to </span>figure out the density<span> (p = m / v). You may also need to know </span>how to calculate<span> the volume of a </span>solid s<span>o use the formula</span>