Normal polarity
Explanation:
Earth's magnetic field used to be twice as strong 1.5 billion years ago as it is today and Earth's temperature other than what the geologists see from the 'normal' pattern. It has been noticed that some volcanic rocks were magnetized in opposite direction to the direction of the local Earth's field. It is clear that the Earth has experienced the normal polarity 1.5 years ago but at that time, the Earth's polarity was poorly understood.
A normal heart rate ranges between 60-100 beats per minute. The higher the heart rate is, the faster the blood is pumping through the heart. When exercising a persons heart will be higher because the brain and the muscles in the body are in need of oxygen so the heart needs to pump faster in order to sustain optimal performance.<span />
C. If an is added to the water in a vase of daffodils, then the flowers' wilting time will not change because aspirin has no effect on the wilting time of daffodils.
This is the correct answer