[haifaa]

cardiovascular diseases (diseases of the heart and blood vessels) are the leading case of death worldwide. to address this problem,biomedical engineers have designed various artificial hearts,and some day surgeons may routinely implant these in patients whose own hearts are failing.before implanting such a device in a patient, asurgeon needs to have an idea of how long it might be expected to work before needing to be replaced.if an artificial heart is capable of pumping at least

( 8×10اس 6)

liter of blood before failure,how long will it probably last in a patient if their average heart rate is 72 beats per minutes, and average stroke volume

(the amount of blood pumped with each stroke)

?is 70 mi