The answer is that <span>healthy </span>legs<span> have </span>veins<span> with smooth, elastic walls that </span>are<span> perfectly designed to </span>adapt<span> to the changes in pressure within a </span>vein<span>. </span>Veins<span> have </span>valves<span> that keep blood moving in one direction: back toward the heart. As the </span>leg<span> muscles </span>are<span> activated, the </span>venous valves<span> open to </span>allow<span> one-way flow in the direction of the heart.</span>
The appropriate response is heart rates. A typical resting heart rate for grown-ups ranges from 60 to 100 pulsates a moment. By and large, a lower heart rate very still infers more productive heart capacity and better cardiovascular wellness. For instance, an all around prepared competitor may have an ordinary resting heart rate more like 40 thumps a moment.
5) C
6) B
would be the answers for the two questions hope it helped
