Answer:
Target Heart Rate
Explanation:
Target heart rate is generally expressed as a percentage (usually between 50 percent and 85 percent) of your maximum safe heart rate. The maximum rate is based on your age, as subtracted from 220. So for a 50-year-old, maximum heart rate is 220 minus 50, or 170 beats per minute.
Abiotic are the nonliving things in an ecosystem such as climate and soil type.
After reading the following options, the correct one is the third option, PET scans will use tracers to inject in a vein in someone's arm. Then, the organs as well as tissues will absorb the tracer. This information makes the third option correct because PET scans mostly work with your tissues to see if there are any diseases someone may have in their body.
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Peaculiar
