During the period of ejection in the cardiac cycle (when blood is leaving the ventricles), the atrioventricular valves are and the semilunar valves are .

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from this experiment, we conclude that hand watering plants are better than watering by sprinklers.

manual watering is the easiest way to water your plants and potted flowers. it requires very little equipment because a simple watering can or a garden hose to which is attached a gun or a spray nozzle is enough. be careful, however, because the main disadvantage of this type of watering is that it is uneconomical and it is impossible to know if the plant has been sufficiently watered.

with sprinklers, the chore of manual watering is over. as a bonus, it reduces the amount of water used and therefore reduces your bill. placed on the ground, flying, fixed or buried.