A student measures the range of sound frequencies that the human ear can hear by playing sounds for volunteers between 10 and 30,000 Hertz and asking them to raise their hand if they were able to hear it. What type of variable is the
independent variable in this experiment?

what have fossils ever done for you

its probably to later but whats the question

you know that this symptom is misleading and quite often is related to: heart attack

a heart attack is a condition that occurs when the blood flow that transports oxygen to the heart muscle is damaged or cut off completely. the coronary arteries that supply the heart muscle with blood flow can be blocked by the accumulation of plaque. also, when the plaque within the heart artery breaks, it creates blood clot that can also hinder the blood flow. men that are over 45years of age and women that are over 55years of age are at risk of having a heart attack. the symptoms of a heart attack include chest discomfort, chest pain, coughing, and shortness of breath.