Short Answer: T<span>he ability to see, hear, or become aware of something through the senses.</span>
Yes it does the chemicals in whatever you are smoking are more than likely altered from what it originally was, therefore the chemicals start to taint the blood vessels and damage them permanently.
Answer:
Subtract your heart's resting rate from your maximum rate. For example, if you are 40 years old, subtract that number from 220; your maximum rate is 180. Next, subtract your resting rate or 80 in this example. Your heart-rate reserve is 100 beats per minute.