Answer:
1. B
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.
2. B
You can measure exercise intensity using target heart rates, the talk test, or the exertion rating scale. For maximum health benefits, the goal is to work hard, but not too hard, described as moderate intensity by Australia's Physical Activity and Sedentary Behaviour Guidelines.
