<span>The esophagus runs behind the windpipe (trachea) and heart</span>
Biomass decays and produces gases such as nitrogen and very small amount of helium. in many places it is used to produce energy by comustion.it's mass becomes less and a layer of humus type organic substance is left on the soil....if i'm not incorrect :)
Gravitational waves are ripples in spacetime. They are created whenever objects with mass move. Hope this helps :)
Your answer is D. Mustard Seeds. They grow in the the Middle East.
