Answer:
Air speed of bird is
mph
Explanation:
let the speed of the bird in still air be "X"
Speed of the bird when it flies in the direction of flow of wind 
Speed of the bird when it flies in the opposite direction of flow of wind 
The total time taken is equal to
minutes
hours
The distance in miles is equal to
miles

On solving the above equation, we get -

Air speed of bird is
mph
Answer:
When an impulse reaches the muscle fibres of a motor unit, it stimulates a reaction in each sarcomere between the actin and myosin filaments. This reaction results in the start of a contraction and the sliding filament theory.
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Because earth has natural cycles it goes through with ecosystems, and when we get involved with trying to help one spectrum of the natural world (rabbits for example) we hurt another (wolves, by over feeding, increasing the population, then exhausting the population of rabbits over a time.)
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Answer:
D. membrane-enclosed organelles
Explanation: