Answer:
<em>Nitrogen</em><em> </em><em>dioxide</em><em> </em><em>is </em><em>an </em><em>irritant </em><em>gas,</em><em> </em><em>which </em><em>at </em><em>high </em><em>concentration</em><em> </em><em>cause </em><em>inflammation </em><em>of </em><em>the </em><em>airways.</em><em> </em><em>.</em><em>.</em><em>.</em><em> </em><em>Nox </em><em>gases </em><em>react</em><em> </em><em>to </em><em>form </em><em>smog </em><em>and </em><em>acid </em><em>rain </em><em>as </em><em>well </em><em>as </em><em>being </em><em>central </em><em>to </em><em>the </em><em>formation</em><em> </em><em>of </em><em>fine </em><em>particles </em><em>and </em><em>ground</em><em> </em><em>level </em><em>ozone,</em><em> </em><em>both </em><em>of </em><em>which</em><em> </em><em>are</em><em> </em><em>associated</em><em> </em><em>with </em><em>adverse </em><em>health</em><em> </em><em>effects.</em>
Answer:
Students who take a PE class and who will be eating sugary snacks before PE.
Explanation:
The control variable (or control group) is an experimental element which is constant or unchanged throughout the course of the experiment.
The option "students who take PE class and who will be eating sugary snacks before PE" will remain unchanged and constant because the whole point of the experiment is to see the effects on students performance in PE after eating sugary snacks.
Hope this helps :)
<span>Firstly, it is the only substance on Earth that is in liquid form at the temperatures commonly found on the Surface of our planet. Secondly, it is a superb solvent, meaning that other substances regularly and easily dissolve into it. This allows water to carry nutrients to cells, and carry waste away from them.</span>
Wild animal meat (small game animals), various vegetables, (corn, squash, etc.)
I would say the answer to your question is C) primary succession,because p<span>rimary succession begins on rock formations, such as volcanoes or mountains, or in a place with no organisms or soil. </span>