B, when humans exhale we put out carbon dioxide.
C.)The waste of animals returns nitrogen to the nitrogen cycle.
C. <span>"It came in his mind / to bid his henchmen a hall uprear"
A. </span><span>"How ceaselessly Grendel / harassed Hrothgar . . ."
B. </span><span>"'Who are ye, then, ye arméd men, / mailéd folk . . .'"
D. </span><span>"'To Hrothgar I / in greatness of soul would succor bring'"</span>
They are unicellular prokaryotes, that are lacking membrane bound organelles.
<span>The gradient of a stream </span>depends on its slope<span> and </span>discharge<span>, which in turn can explain the carrying power of a </span>stream.